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HIV in Vietnam: The Evolving Epidemic and the Prevention Response, 1996 Through 1999

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Tiêu đề HIV in Vietnam: The Evolving Epidemic and the Prevention Response, 1996 Through 1999
Tác giả Vu Minh Quan, A. Chung, Hoang Thuy Long, Timothy J. Dondero
Chuyên ngành Public Health
Thể loại Journal Article
Năm xuất bản 2000
Thành phố Philadelphia
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Số trang 10
Dung lượng 292,34 KB
File đính kèm khk.zip (272 KB)

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continues to evolve, with rapid increases in infection in the north, a region previously little affected. In this paper, we summarize the recent changes through 1999 and describe the national response to the epidemic. Vietnam is a country of 76.7 million people, according to the Vietnamese Ministry of Health. It is divided into 61 administrative units that comprise 57 provinces and four major cities (Hanoi, Hai Phong, Da Nang, and Ho Chi Minh City HCMC), expanded from a total of 53 such units in 1996. A summary of the country’s demographic characteristics relevant to HIV has been published (1)

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HIV in Vietnam: The Evolving Epidemic and the Prevention

Response, 1996 Through 1999

*‡Vu Minh Quan, *A Chung, †Hoang Thuy Long, and ‡Timothy J Dondero

*National AIDS Committee of Vietnam, Hanoi; †National Institute of Hygiene and Epidemiology, Hanoi, Vietnam; and ‡Division

of HIV/AIDS Prevention—Surveillance and Epidemiology, National Center for HIV, STD, and TB Prevention, U.S Centers for

Disease Control and Prevention, Atlanta, Georgia, U.S.A.

Objectives: To describe epidemiologic patterns and trends in HIV infection in

Vietnam from 1996 through 1999, and to summarize the national response to the epidemic

Methods: We reviewed nationwide HIV case reports, and we analyzed annual

seroprevalence among different sentinel populations in 21 provinces, using the␹2test for linear trend to assess trends in HIV prevalence HIV prevention efforts were also reviewed

Results: Through 1999, 17,046 HIV infections, including 2947 AIDS cases and

1523 deaths had been reported in Vietnam The cumulative incidence rate for the country was 22.5 per 100,000 population Injection drug users (IDUs) represented 89.0% of all those for whom risk was reported before 1997 and 88.0% in the period

1997 to 1999 In 1999, HIV prevalence rates among IDUs ranged by province from 0%

to 89.4% Significantly increasing HIV trends among IDUs (p < 05) were found in 14

of the 21 sentinel provinces during 1996 to 1999 HIV prevalence among commercial sex workers (CSWs) ranged from 0% to 13.2%, increased significantly in 6 of 21 provinces In 1999, prevalence among pregnant women, blood donors, and military recruits were 0.12%, 0.20% and 0.61%, respectively Major prevention activities in-clude mass information; peer education and outreach among groups at increased risk;

availability of low-cost syringes and condoms through pharmacies; needle exchange pilot projects; widely available treatment for sexually transmitted diseases; antibody screening of blood for transfusion; and free medical treatment at government hospitals

Discussion: The HIV epidemic continues to evolve rapidly, intensifying among

IDUs and increasing among CSWs Serosurveillance indicators of HIV in the popu-lation at large continue to indicate the relatively slow extension beyond those at highest risk Immediate, intensive preventions in high-risk groups may decelerate expansion to the broader population

Key Words:

HIV—AIDS—Vietnam—Asia—Prevalence—Surveillance—Epi-demiology—Trend—Prevention

The HIV epidemic has emerged rapidly in Vietnam

since the first infection was detected in 1990 The

epi-demiologic situation through the end of 1996 has been

summarized elsewhere (1) Since that time, the epidemic

continues to evolve, with rapid increases in infection in the north, a region previously little affected In this pa-per, we summarize the recent changes through 1999 and describe the national response to the epidemic

Vietnam is a country of 76.7 million people, according

to the Vietnamese Ministry of Health It is divided into

61 administrative units that comprise 57 provinces and four major cities (Hanoi, Hai Phong, Da Nang, and Ho Chi Minh City [HCMC]), expanded from a total of 53 such units in 1996 A summary of the country’s demo-graphic characteristics relevant to HIV has been pub-lished (1)

Address correspondence and reprint requests to Vu Minh Quan,

Division of HIV/AIDS Prevention—Surveillance and Epidemiology,

National Center for HIV, STD, and TB Prevention, Centers for Disease

Control and Prevention, 1600 Clifton Road, Mailstop E-46, Atlanta,

GA 30333, U.S.A.; e-mail: vaq1@cdc.gov

Vu Minh Quan is currently an officer in the Epidemic Intelligence

Service [EIS] Program and Division of HIV/AIDS Prevention at the

Centers for Disease Control and Prevention.

Manuscript received March 28, 2000; accepted August 2, 2000.

360

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Social changes in Vietnam continue to occur as the

economy advances Many of these changes have been

beneficial, but there are unwanted consequences as well

Drug use continues to be a concern, as it is throughout

much of Asia During the past decade, heroin has

emerged as one of the drugs most commonly used, and

injection drug use remains the principal mode of HIV

transmission in Vietnam Increases in investment and

business, along with increased numbers of visitors, have

helped the economy but have also encouraged

commer-cial sex

AIDS-related activities, including surveillance,

pre-vention, and treatment, are coordinated and funded

na-tionally by the National AIDS Committee of Vietnam,

which is made up of numerous government ministries

and mass organizations At the provincial and city levels,

AIDS activities are coordinated by the provincial or city

AIDS committee, which includes the local counterparts

of the same groups that comprise the National AIDS

Committee

AIDS cases are reported to the respective provincial

AIDS committee in two ways: hospitals report AIDS

cases to the provincial Department of Health (which

par-ticipates in the provincial AIDS committee); additional

cases are detected by the provincial center for hygiene

and epidemiology in the course of public health

follow-up of persons who have tested HIV positive

HIV infection is detected through several means,

in-cluding serologic surveys, counseling and testing,

diag-nostic procedures, evaluation of partners of HIV-infected

persons, and occasional epidemiologic field

investiga-tions Within a province or city, most of these public

health activities are conducted by the provincial Center

for Hygiene and Epidemiology, which is part of the pro-vincial department of health

Reports of HIV infection as well as reports of AIDS cases and deaths are provided weekly by the provincial center for hygiene and epidemiology to the Pasteur In-stitute serving the region or (for the north) to the Na-tional Institute for Hygiene and Epidemiology (NIHE) Compilation of all data are done at NIHE, and the results are provided to the National AIDS Committee

Cases of sexually transmitted diseases (STD), primar-ily those seen at public-sector provincial STD centers and clinics, are reported to the National Institute for Der-matology and Venereology, which analyzes the data and provides them to the Ministry of Health and the National AIDS Committee

HIV AND AIDS REPORTING

Through 1999, 17,046 HIV infections, including 2947 AIDS cases and 1523 deaths, were reported The number

of reported HIV infections per year continues to increase rapidly, whereas AIDS cases and deaths climb more slowly (Fig 1) The 1999 cumulative incidence rate for the country as a whole was 22.5 per 100,000 population, compared with only 7.0 per 100,000 population in 1996 (1)

Infections have been reported from all of the country’s

61 provinces and major cities Most of the recent in-crease in reported HIV infections has taken place in the north, a region where HIV was very limited even 3 years before Indeed, by the end of 1999, of the 10 areas with the largest cumulative numbers of cases, five were in the

FIG 1. Reported HIV infections, AIDS cases, and AIDS deaths, Viet-nam, by year of report, 1990 through 1999.

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north; 3 years earlier, no northern province or city was

among the top 10 areas The three areas with the highest

cumulative incidence rates of reported HIV (Fig 2) are

in the north: Quang Ninh (222 per 100,000 population),

Lang Son (81 per 100,000 population) and Hai Phong

(70 per 100,000 population)

The most dramatic recent increase in HIV infections is

associated with injection drug use and has occurred

pri-marily in the northeastern corner of the country In the

area that includes the provinces of Lang Son, Thai

Nguyen, Bac Giang, Quang Ninh, Bac Ninh, Hanoi,

Hung Yen, Hai Duong, and Hai Phong, the number of

newly detected infections has increased from 8 in 1995,

to 126 in 1996, to 969 in 1997, to 2043 in 1998, to 2885

in 1999 During the same 5 years, the proportion of

newly detected infections rose from 1% of the country’s

total in 1995, to 9% in 1996, to 32% in 1997, to 55% in

1998, and leveled to 52% in 1999

The principal risk for HIV in Vietnam remains

injec-tion drug use, which accounts for 88.3% of all cases for

which risk has been reported or can be inferred

Al-though there is some geographic variation in frequency,

infections associated with injection drug use far exceed the infections associated with all other risks except in the southern provinces of An Giang and Can Tho, and this predominance has not changed over time; injection drug users (IDUs) represented 89.0% of all persons for whom risk was reported before 1997 and 88.0% in the period from 1997 to 1999

Although currently much less frequent than drug-related transmission, the second most common risk re-mains sexual transmission, principally heterosexual transmission Of all infections reported through 1999, 5.0% of cases with risk information were in commercial sex workers (CSWs); an additional 3.6% of cases were in patients being seen clinically for an STD (for whom sexual risk is assumed to be the source of transmission), and another 2.3% were in workers in the entertainment industry or others thought to be at increased sexual risk Thus, at least 10.9% of cases with known or reasonably presumed risk seem to have been sexually acquired

No case of HIV has been determined to be associated with sexual transmission between men Although this risk may be underascertained, the frequency of

male-to-FIG 2. Cumulative HIV incidence per 100,000 population by prov-ince, Vietnam, 1996 and 1999 Map does not illustrate small offshore is-lands.

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male HIV transmission still seems to be very low

Chil-dren thought to have acquired HIV infection from their

mothers (24 cases) remain a small part (0.2%) of the

epidemic thus far HIV infection resulting from

transfu-sion of blood or blood products has not yet been

de-tected

Of those reported with HIV infection, 86.7% have

been men Distribution by sex has not changed

apprecia-bly: 84.4% men during 1990 to 1996 and 87.9% during

1997 to 1999 However, infections are occurring

increas-ingly in younger persons, especially in those 20 to 29

years old (Fig 3)

Although reported HIV infections and AIDS cases

il-lustrate the geographic, demographic, and risk

character-istics of the epidemic, the number of detected, reported

infections and AIDS cases will always be a fraction of

the total in the country The National AIDS Committee

estimates that in reality 120,000 to 140,000 infections

existed in Vietnam by the beginning of 1999

SEROSURVEILLANCE

An important part of monitoring HIV in Vietnam is

the sentinel serosurveillance program (2) As part of this

program, in 1999, 20 provinces and major cities

con-ducted annual or semiannual HIV surveys in sentinel

populations (IDUs, CSWs, STD patients, tuberculosis

[TB] patients, pregnant women, and military recruits)

The annual target sample size (not always reached in

some provinces) is 400 each for IDUs, CSWs, STD

pa-tients, and TB papa-tients, and 800 each for pregnant

women and military recruits, respectively Data from the

screening of blood donors are also available in many

sentinel provinces Serosurveys were begun in some

provinces in 1994; by 1999, they were being conducted

in all 20 sentinel areas In addition, Quang Ninh prov-ince, not a formal part of the sentinel surveillance pro-gram, has also conducted surveys since 1996 Serosur-veillance data are more reliable than case reporting for evaluating trends, because the methods for survey sam-pling remain essentially consistent, whereas the com-pleteness of case reporting, which is affected by factors aside from the epidemiologic situation, can differ from year to year We used the␹2

test for linear trend to assess trends in HIV prevalence in the 20 sentinel provinces and Quang Ninh province, from 1996 through 1999 Sentinel surveillance among IDUs continues to indi-cate high levels of infection associated with drug injec-tion (Table 1) The epidemic among IDUs has intensified

in 14 of the 21 provinces surveyed (Fig 4) In the central region, where HIV prevalence among IDUs was moder-ately high by 1996, the levels by 1999 had uniformly, and in some places dramatically, increased (e.g., Binh Dinh, from 23.3% to 71.1%; Khanh Hoa, from 50.8% to 89.4%) In the south, the HIV prevalence among the sentinel IDU populations increased significantly in four provinces, An Giang, Can Tho, Kien Giang and Vung Tau-Ba Ria, but stabilized in three areas, of which HCMC and Dong Nai already had high prevalences However, the greatest overall change in HIV prevalence has been the explosive increase from 1996 through 1999

in 7 of 9 provinces surveyed in the north (Table 1) The most dramatic increases have occurred in Quang Ninh and Hai Phong

The two sentinel indicators of sexual transmission risk, surveys among CSWs and surveys among STD clinic patients, continue to indicate that sexual trans-mission is a distant second to transtrans-mission associated

FIG 3. Reported HIV infections

by age group, Vietnam, by year,

1990 through 1999.

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with injection drug use, again, a pattern that is consistent

with HIV case reports Nonetheless, the prevalence of

HIV among CSWs has increased in several areas (Table

1), although to levels well below those in some other

southeast Asian countries (3–5) The HIV prevalence

among sentinel groups at increased sexual risk has been

highest in the south, where sex-related transmission was

already evident by 1996 In 1999, HIV prevalence

among CSWs reached 5.0% to 13.2% in some areas,

compared with 4.1%, the highest level in 1996 The

prevalence in CSWs increased significantly in four of

seven Mekong delta provinces from 1996 through 1999

(Table 1, Fig 4) Outside the southern region, HIV

prevalence among CSWs is still very low and stable (10

of 14 northern and southern provinces have rates less than 1% in 1999) The exceptions are in the north: Hanoi (from 0.1% in 1996 to 6.0% in 1999) and Hai Phong (from 0.8% to 2.6%) HIV infection also seems to be increasing among STD patients (who are mostly men) in some of the southern sentinel provinces, although the increase is significant in only two (An Giang and Dong Nai; Table 1) In 1999, the prevalence among STD pa-tients in the central region continued to be as low as it had been in 1996 In the north, the prevalence among STD patients in 1999 is generally low, except in Hanoi (2.0%), Hai Phong (5.5%), and Quang Ninh (3.9%)

FIG 4. Significant increases* in HIV prevalence among injection drug users, commercial sex work-ers, and sexually transmitted dis-ease patients in sentinel prov-inces, Vietnam, 1996 through

1999 Map does not illustrate small offshore islands.

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During the past 3 years, Quang Ninh, in the northeast,

has emerged as the province with the second largest

number, and the highest cumulative incidence rate, of

reported HIV infections in the country Serosurveys

con-ducted by the provincial AIDS Committee have shown

an explosive pattern among IDUs: from 0% in 1996 to

62.4% in 1997, 65.9% in 1998, and 64.9% in 1999 (data

provided by Quang Ninh provincial AIDS Committee),

prevalence levels that are consistent with case reports in

that province and with the serosurveillance data from

nearby sentinel provinces (Table 1) Of 206

HIV-infected persons detected in the first half of 1997, 203

(99%) were male, the median age was 22 (range, 15–37) Risk information was available for 155 persons, of whom

149 (96%) were IDUs (National AIDS Committee, un-published data) In the neighboring port city of Hai Phong, an upsurge in HIV prevalence among IDUs in

1998 occurred 1 year after that in Quang Ninh, jumping

to 32.5% from 0.9% in 1997 Similar to the pattern in Quang Ninh the previous year, of 101 persons in Hai Phong who had been diagnosed with HIV in first 3 months of 1998, 91% were <30 years old, and 84% were IDUs (National AIDS Committee, unpublished data) In

1999, HIV prevalence began to rise among IDUs in

Ha-TABLE 1 Changes in HIV seroprevalence among injection drug users, commercial sex workers and sexually transmitted disease (STD) patients

in Vietnam, 1996 through 1999, a by province

Injection drug users percentage positive

(n)

Commercial sex workers percentage positive

(n)

STD patients percentage positive

(n)

1996 1997 1998 1999 p Value b

1996 1997 1998 1999 p Value 1996 1997 1998 1999 p Value

Northern region

Hanoi 0.6 2.4 3.3 13.5 <.0001 0.1 0.8 3.8 6.0 <.0001 0.4 0.0 0.0 2.0 NS

(538) (419) (400) (200) (1035) (357) (400) (200) (909) (366) (400) (200)

Ha Tinh — 0.0 5.2 9.6 012 0.0 0.0 0.0 0.6 NS 0.0 0.0 0.0 0.0 NS

(0) (15) (439) (281) (283) (460) (548) (163) (279) (450) (434) (225) Hai Phong 0.1 0.9 32.5 64.0 <.0001 0.8 0.0 1.1 2.6 044 0.2 0.0 2.8 5.5 <.0001

(942) (325) (496) (203) (251) (361) (354) (192) (1370) (373) (400) (253) Lang Son 9.2 21.7 14.5 8.5 NS 1.0 0.0 — 0.0 NS 0.0 0.0 4.2 1.0 002

(761) (641) (234) (200) (96) (15) (0) (32) (737) (222) (48) (200) Lao Cai 0.0 0.0 0.0 1.2 NS 0.0 0.0 0.0 0.5 NS 0.0 0.0 0.0 0.0 NS

(296) (581) (615) (603) (171) (87) (301) (206) (139) (83) (199) (55) Nam Dinh 0.5 0.5 2.5 12.4 <.0001 0.0 0.0 0.0 0.0 NS 0.1 0.6 0.5 1.9 017

(655) (431) (404) (170) (228) (222) (375) (16) (781) (502) (439) (162) Quang Ninh 0.0 62.4 65.9 64.9 <.0001 — — 0.4 0.5 NS 0.0 2.1 9.5 3.9 <.0001

(95) (210) (545) (444) (0) (0) (450) (402) (631) (869) (506) (412) Thai Nguyen 0.0 2.7 70 7.6 <.0001 0.0 0.0 0.5 0.0 NS 0.0 0.0 0.0 0.0 NS

(273) (701) (427) (264) (214) (410) (206) (202) (201) (425) (201) (200) Thanh Hoa 0.0 0.0 0.3 9.5 <.0001 0.0 0.0 0.0 0.0 NS 0.0 0.0 0.0 0.0 NS

(82) (288) (696) (433) (1034) (743) (132) (62) (546) (1213) (397) (190) Central Region

Binh Dinh 23.3 56.7 62.9 71.1 <.0001 0.7 1.2 2.1 1.1 NS 0.0 0.0 0.0 0.5 NS

(60) (231) (175) (152) (146) (333) (190) (174) (405) (207) (181) (184)

Da Nang 38.5 68.6 85.3 48.8 NS 0.0 0.0 0.5 0.0 NS 0.0 0.0 0.0 0.5 NS

(65) (121) (75) (80) (422) (450) (200) (200) (500) (450) (153) (195) Dac Lac 24.1 45.2 41.8 41.0 003 1.4 1.7 0.0 1.7 NS 0.0 0.0 0.0 0.0 NS

(191) (188) (110) (122) (70) (182) (73) (60) (35) (44) (23) (15) Khanh Hoa 50.8 67.6 81.8 89.4 <.0001 0.5 0.0 0.5 0.5 NS 1.1 0.0 1.0 0.6 NS

(65) (111) (121) (47) (184) (333) (208) (212) (263) (289) (201) (154) Thua Thien-Hue 0.0 0.8 2.5 0.0 NS 0.0 0.0 0.9 0.0 NS 0.6 0.0 1.0 0.9 NS

(84) (260) (79) (66) (88) (352) (116) (69) (172) (242) (98) (110) Southern Region

An Giang 4.7 5.1 16.3 12.8 <.0001 4.1 3.7 14.7 13.2 <.0001 1.3 3.6 6.0 6.5 <.0001

(665) (526) (516) (313) (660) (512) (532) (326) (909) (504) (315) (185) Binh Duong 5.7 5.6 4.3 7.7 NS 0.9 1.0 1.0 1.7 NS — — 0.7 2.5 NS

(652) (342) (600) (300) (433) (582) (600) (300) (0) (0) (138) (200) Can Tho 1.4 2.2 2.0 5.6 039 2.8 1.6 5.5 5.3 003 0.2 1.5 2.0 0.0 NS

(213) (320) (196) (124) (291) (1004) (236) (206) (622) (259) (202) (70) Dong Nai 28.8 22.7 23.7 16.3 NS 0.5 1.5 0.8 1.4 NS 0.3 0.6 0.0 2.9 013

(80) (308) (338) (135) (386) (458) (372) (71) (402) (332) (241) (137)

Ho Chi Minh City 36.9 28.3 44.8 26.9 NS 1.2 2.8 3.8 4.9 0001 0.8 1.0 1.8 1.0 NS

(1199) (924) (250) (238) (1397) (834) (399) (81) (1549) (1192) (221) (105) Kien Giang 1.0 13.6 14.3 16.5 <.0001 1.3 12.1 1.3 2.5 NS 0.3 1.1 2.5 1.0 NS

(984) (376) (400) (200) (541) (387) (400) (200) (383) (275) (400) (200) Vung Tau-Ba Ria 6.5 5.6 16.7 37.5 <.0001 0.8 0.8 2.7 5.0 0003 0.4 1.2 0.0 0.0 NS

(245) (450) (395) (200) (248) (497) (402) (200) (243) (422) (400) (200)

a

1999 Data were provisional.

b␹ 2

for linear trend; p value shown if a significant difference found NS, not significant (pⱖ 05).

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noi and other provinces in the region (Table 1, Fig 4).

Although the time lag varies from province to province,

the pattern of HIV prevalence in IDUs indicates a rapidly

expanding HIV epidemic in the north, which may extend

beyond IDUs to those at increased sexual risk

Serosurveillance indicators of HIV in the population at

large (pregnant women, military recruits, blood donors)

continue, in general, to indicate a relatively slow

exten-sion of HIV beyond those at high risk Of 14,921

preg-nant women tested in the 20 provinces (1999 data from

Hanoi not available), only 18 (0.12%) had positive

re-sults in 1999, a slow but significant increase (p⳱ 017)

over the past 4 years (0.04% in 1996; 0.12% in 1997;

0.09% in 1998) The highest rates for pregnant women in

1999 were in Quang Ninh (0.7%) in the north, and in An

Giang (0.4%) and Binh Duong (0.3%) in the south,

whereas the highest rates in 1996 were both in the south

(HCMC, 0.2%; An Giang, 0.2%) There is no statistically

significant change in HIV prevalence among pregnant

women in any individual province from 1996 though

1999, despite the significant increase for the provinces as

a group For military recruits, among approximately 800

tested per province, the overall rate in 1999 was 0.61%

(92 HIV positive of 14 989 tested), significantly higher

(p < 0001) than the rates in 1996 (7 [0.04%] of 17,430),

1997 (23 [0.13%] of 17,273), 1998 (34 [0.20%] of

17,281) The highest rates were found in three northern

provinces (Quang Ninh, 5.0%; Lang Son, 2.5%; Hai

Phong, 0.6%) and in two southern provinces (Kien

Giang, 1.5%; Vung Tau-Ba Ria, 1.0%) All five

prov-inces had either significantly increasing trends in HIV

prevalence from 1996 to 1999 among IDUs or already

had prevalence rates higher than 20% during this period

Because IDUs are not excluded from medical screening

for military service, some IDUs may be included in the

tested population HIV among blood donors remains

in-frequent: 108 (0.08%) positive results from 128,808

units tested in 1996; 114 (0.09%) positive of 133,832 in

1997; 181 (0.12%) positive of 152,094 in 1998; and 260

(0.20%) positive of 132,705 in 1999 The increase over

the 4-year period, although small, is statistically

signifi-cant (p < 0001).

Serosurveillance among TB patients gives an indirect

and lagging indication of the evolution of the HIV

epi-demic Through 1996, HIV prevalence among TB

pa-tients was very low At that time only in HCMC (1.3%)

and Khanh Hoa province (1.4%) were prevalence rates

>1% (1) In 1999, HIV prevalence among TB patients

remains generally low, mostly <3%, with 12 sentinel

provinces’ rates at or near 0% Only two provinces had

higher HIV prevalence, Quang Ninh (6.8%) and An

Giang (3.8%) HCMC had previously had a high

lence (11.8% in 1998), but in 1999 the measured preva-lence was down (2.9%) Thus, this surveillance indicator

of the duration, as well as of the clinical impact, of the epidemic confirms that HIV has been established rela-tively recently in most parts of the country and is just beginning to have a clinical impact

MOLECULAR EPIDEMIOLOGY

The virus responsible for the epidemic in Vietnam remains almost exclusively HIV-1 subtype E (1,6–8) This is similar to, and presumably an extension of, the pattern in adjacent Cambodia (9–11), and other countries

in the southeast Asian region, including Thailand, (al-though Thailand also has subtype B⬘ infection, particu-larly in IDUs in central Thailand) (12–14) Indeed, the viral isolates from Vietnam are genetically very close to those from Cambodia and from Thailand (7,10,11) In Quangxi, the Chinese province bordering Vietnam on the north, subtype E also predominates in IDUs, although subtype B⬘ has been found in blood donors (15)

SEXUALLY TRANSMITTED DISEASES

STDs indicate the degree of sexual risk for HIV in-fection and facilitate its transmission STD treatment re-mains an important component of HIV prevention (16) Reported STDs, although assumed to underestimate the true frequency significantly, have increased rapidly in the 1990s There were large increases in case reports in

1993 and in 1997 to 1998, after extensive training courses in the diagnosis and treatment of these diseases The total of reported STDs for the country was 71,274 for 1997 and 102,277 in 1998 However, the National Institute of Dermatology and Venereology estimates that the true figure was closer to a million cases (Pham Van Hien, personal communication) STD services are pro-vided through government-supported primary health care facilities at provincial level (61 facilities), district level (597), and at local (commune) level (>10,000) Because syndromic STD management is used in primary health care, as recommended by the World Health Organization (17,18), specific STD diagnoses are usually available only from larger clinical facilities at the provincial and national levels Many STDs are treated through the pri-vate sector, but little information is available to national authorities on either the methods of diagnosis or the numbers of patients seen

A few surveys have been done to enhance STD sur-veillance Among pregnant women in 1995 in Hanoi and HCMC, STD prevalence rates were low: syphilis, 0.2%

in Hanoi and 0.5% in HCMC; gonorrhea, 0.3% in Hanoi

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and 0.7% in HCMC; chlamydia, 2.2% in Hanoi and 2.5%

in HCMC Not surprisingly, STD prevalence rates are

much higher among CSWs in rehabilitation centers than

among other women; for example, syphilis rates range

from 20% to 40% in HCMC and Hanoi (unpublished

WHO Report, Summary of Rates for Sexually

Transmit-ted Disease, Vietnam, Aug 1998)

PREVENTION

The HIV prevention strategy in Vietnam begins with

the structural organization and coordination of the

prin-cipal AIDS-related activities through the national and the

provincial AIDS committees As noted earlier, these

committees include multiple sectors of the national or

provincial governments Leadership of the AIDS

com-mittees is at the second highest level of the civil

admin-istrative authority for the country or the province, a

deputy prime minister, to ensure collaboration between

sectors and consistency of approach The total current

annual government allocation for HIV/AIDS control

ac-tivities ranges from $4 to $5 million U.S Additional

support has been provided through international and

non-governmental organizations

In addition to HIV surveillance, the major prevention

activities are as follows:

Mass information and health education regarding HIV

risks and how to avoid them

Peer education and outreach among groups at increased

risk, particularly IDUs and CSWs

Voluntary HIV counseling and testing through each

province’s center for hygiene and epidemiology

Ready availability of low-cost needles and syringes

through pharmacies

Needle exchange pilot projects for IDUs in Hanoi and

HCMC

A pilot methadone maintenance program in Hanoi

Availability of condoms at low cost ($0.02–0.05 U.S per

condom) at pharmacies throughout the country

Desensitizing the discussion of condoms through public

education campaigns and social marketing

Widely available STD treatment

Antibody screening of blood for transfusion

Free medical treatment at provincial hospitals, including

zidovudine (AZT), some didanosine (ddI), and

treat-ment of opportunistic infections

In 1995, a study was conducted on the feasibility and

effectiveness of needle exchange programs in Hanoi and

HCMC (19) Recent studies indicated that needle sharing

remains frequent among drug injectors (20) A

small-scale trial of methadone treatment was conducted by the

Vietnamese National Institute of Mental Health In 1999, the Vietnamese National AIDS Committee began a large-scale intervention, including peer outreach, among IDUs and CSWs in 20 provinces

The safety of blood for transfusion is ensured through routine screening for HIV as well as for hepatitis B, syphilis, and malaria, plus (in some areas) hepatitis C Transfusions are performed at 84 provincial and other major hospitals as well as at 442 district hospitals All these facilities perform HIV testing (particle agglutina-tion or a rapid test in most facilities, enzyme immuno-assay in some) Surgery requiring transfusion is occa-sionally performed at other district hospitals, which de-pend on blood screened at better equipped facilities in the vicinity

In 1997, approximately 300,000 units of blood were collected and screened Although an appreciable propor-tion of donapropor-tions is made by paid professional donors, it

is the policy of the National AIDS Committee to encour-age voluntary donation In 1996, 62% of donations were from professional donors; in 1997 and 1998, this propor-tion decreased to 53% and 37%, respectively (Napropor-tional AIDS Committee, unpublished report) Fortunately, as mentioned, HIV remains relatively rare in blood donors About 7% of the total AIDS budget is applied to the treatment of HIV-infected persons, primarily patients who have clinical AIDS In 1998, government facilities provided free treatment for 690 patients Antiretroviral therapy at this time is monotherapy (primarily with zid-ovudine: 33% of patients) or dual therapy (AZT, ddI, and/or indinavir: 54% of patients) Prophylaxis is not routinely offered for opportunistic infections; however, the treatment of such infections is part of clinical care Before the HIV epidemic, TB was already a challeng-ing problem in Vietnam, where an estimated 130,000 cases occur per year By mid-1997, when 882 AIDS cases had been reported (among 6588 HIV-infected people reported by that time), 561 (64%) of these pa-tients had diagnosed TB Of TB papa-tients, 70% had spu-tum-positive pulmonary disease, 15% had sputum-negative pulmonary TB, and 15% had extrapulmonary

TB TB screening, treatment, and preventive therapy of HIV-infected persons and either TB treatment or preven-tive therapy, have not yet been routinely instituted

DISCUSSION

The HIV epidemic continues to intensify among those

at high risk, particularly IDUs, in the central and south-ern regions of the country, areas that were affected by

1996 Of even greater concern, HIV infection has dra-matically increased among IDUs in the north in the past

Trang 9

3 years, as shown by both HIV case reports and

serosur-veillance

Although secondary to infections associated with drug

use, sexually transmitted HIV continues to increase

slowly, largely in the southern areas that had been most

affected several years earlier Despite the increase in

sexually transmitted HIV, the prevalence for the groups

at highest risk is much lower than those for similar

groups in neighboring countries However, the recent

increases in prevalence rates in sentinel surveillance in

Hanoi and Hai Phong indicate the potential for

increas-ing transmission in the north

Despite increases in HIV infection in persons at high

risk, the indicators of HIV in the population at large

(antenatal women, military recruits, and blood donors)

suggest that HIV infection is only slowly reaching the

population outside those at specific high risk However,

with the geographic expansion and intensification of

HIV prevalence in higher risk populations, the danger is

increased, as is the reservoir of infection, for the wider

spread of the epidemic The shift in many parts of the

country toward a younger infected population, primarily

male IDUs, increases the risk of sexual transmission as

these men expose their wives, sex partners, and,

poten-tially, CSWs

More systematic data on STD frequency and trends in

Vietnam would be helpful in evaluating the potential for

expanded sexual transmission Special studies and

sur-veys may be required to supplement case reporting to

obtain a clearer indication of the STD risk patterns in the

population

Consistent with the early picture apparent several

years ago (1), HIV seems to be relatively recent in

Viet-nam, and the clinical impact is only beginning to be

measured The rate of HIV among TB patients remains

quite low However, the increase in TB associated with

HIV in the south, where HIV was first prevalent,

indi-cates what lies ahead as those infected with HIV become

sicker and more subject to opportunistic infections A

reasonably large proportion of AIDS patients, 64%, has

been reported to also have active TB, which is typically

the principal opportunistic infection in many developing

countries (21–23) With the estimated 120,000 to

140,000 HIV infections by 1999, virtually all of whom

will develop AIDS, if 50% to 60% develop TB, there

would be at least 60,000 to 80,000 additional TB cases

over the next few years as a result of existing HIV

in-fections, and more TB cases can be expected from new

HIV infections Considering that the current burden of

TB is 130,000 new cases per year, most not associated

with HIV, the HIV epidemic will have a major impact on

TB services

The almost exclusive finding of subtype E virus is unchanged from previous studies and is consistent with the molecular epidemiologic pattern elsewhere in the re-gion, including countries where the epidemic is much more intense Although the HIV epidemic in Vietnam has developed more slowly than in some nearby coun-tries, Vietnam has been quick to establish surveillance and undertake prevention activities Despite the political complexity of the principal risks for HIV, the govern-ment and the public sector have been open and pragmatic and have kept the public well informed regarding the epidemic, the risks, and the role of prostitution and drug use, and have made the discussion of condom use very public

The HIV epidemic in Vietnam continues to evolve rapidly, although erratically, with recent expansion of the virus into the north and a shift to infection of increas-ingly younger people For most of the country, injection drug use remains the principal risk However even among IDUs, HIV in some areas is still comparatively low Moreover, the epidemic does not seem to have ex-panded very quickly to the broader population, although the potential clearly exists It is equally clear that strenu-ous intervention remains critical in slowing and contain-ing the epidemic That the epidemic has developed later and more slowly in Vietnam than in some other countries

in the region provides cause for hope, as well as the stimulus to maintain and reinforce prevention and moni-toring The people and the government of Vietnam are committed to succeed in this endeavor

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