Nzila Nzilambi

Perinatal Transmission of the Human Immunodeficiency Virus Type 1 to Infants of Seropositive Women in Zaire

To examine perinatal transmission of the human immunodeficiency virus type 1 (HIV-1) in Zaire, we screened 8108 women who gave birth at one of two Kinshasa hospitals that serve populations of markedly different socioeconomic status. For up to one year, we followed the 475 infants of the 466 seropositive women (5.8 percent of those screened) and the 616 infants of 606 seronegative women matched for age, parity, and hospital. On the basis of clinical criteria, 85 of the seropositive women (18 percent) had the acquired immunodeficiency syndrome (AIDS). The infants of seropositive mothers, as compared with those of seronegative mothers, were more frequently premature, had lower birth weights, and had a higher death rate in the first 28 days (6.2 vs. 1.2 percent; P less than 0.0001). The patterns were similar at the two hospitals. Twenty-one percent of the cultures for HIV-1 of 92 randomly selected cord-blood samples from infants of seropositive women were positive. T4-cell counts were performed in 37 seropositive women, and cord blood from their infants was cultured. The cultures were positive in the infants of 6 of the 18 women with antepartum T4 counts of 400 or fewer cells per cubic millimeter, as compared with none of the infants of the 19 women with more than 400 T4 cells per cubic millimeter (P = 0.02). One year later, 21 percent of the infants of the seropositive mothers had died as compared with 3.8 percent of the control infants (P less than 0.001), and 7.9 percent of their surviving infants had AIDS. We conclude that the mortality rates among children of seropositive mothers are high regardless of socioeconomic status, and that perinatal transmission of HIV-1 has a major adverse effect on infant survival in Kinshasa.

Unprecedented Degree of Human Immunodeficiency Virus Type 1 (HIV-1) Group M Genetic Diversity in the Democratic Republic of Congo Suggests that the HIV-1 Pandemic Originated in Central Africa

ABSTRACT The purpose of this study was to document the genetic diversity of human immunodeficiency virus type 1 (HIV-1) in the Democratic Republic of Congo (DRC; formerly Zaire). A total of 247 HIV-1-positive samples, collected during an epidemiologic survey conducted in 1997 in three regions (Kinshasa [the capital], Bwamanda [in the north], and Mbuyi-Maya [in the south]), were genetically characterized in theenv V3-V5 region. All known subtypes were found to cocirculate, and for 6% of the samples the subtype could not be identified. Subtype A is predominant, with prevalences decreasing from north to south (69% in the north, 53% in the capital city, and 46% in the south). Subtype C, D, G, and H prevalences range from 7 to 9%, whereas subtype F, J, K, and CRF01-AE strains represent 2 to 4% of the samples; only one subtype B strain was identified. The highest prevalence (25%) of subtype C was in the south, and CRF01-AE was seen mainly in the north. The high intersubtype variability among the V3-V5 sequences is the most probable reason for the low (45%) efficiency of subtype A-specific PCR and HMA (heteroduplex mobility assay). Eighteen (29%) of 62 samples had discordant subtype designations betweenenv and gag. Sequence analysis of the entire envelope from 13 samples confirmed the high degree of diversity and complexity of HIV-1 strains in the DRC; 9 had a complex recombinant structure in gp160, involving fragments of known and unknown subtypes. Interestingly, the unknown fragments from the different strains did not cluster together. Overall, the high number of HIV-1 subtypes cocirculating, the high intrasubtype diversity, and the high numbers of possible recombinant viruses as well as different unclassified strains are all in agreement with an old and mature epidemic in the DRC, suggesting that this region is the epicenter of HIV-1 group M.

The Prevalence of Infection with Human Immunodeficiency Virus over a 10-Year Period in Rural Zaire

In 1985 we tested 659 human serum samples, collected in the remote Equateur province of Zaire in 1976, for antibody to human immunodeficiency virus (HIV). Five (0.8 percent) were positive, and HIV was isolated from one of these. Follow-up investigations in 1985 revealed that three of the five seropositive persons had died of illnesses suggestive of acquired immunodeficiency syndrome (AIDS), and two remained healthy but seropositive. In 1986, a serosurvey we conducted using a cluster-sampling technique in the same region showed a seroprevalence of 0.8 percent in 389 randomly selected residents. The seroprevalence in 283 prostitutes was 11 percent. Patients with AIDS were identified in various hospitals in the province. Risk factors for AIDS included a greater than average number of sexual partners and residence outside the area. We believe that the long-term stability of HIV infection in residents of rural Zaire suggests that social change may have promoted the spread of AIDS in Africa.

HIV infection and associated risk factors in female prostitutes in Kinshasa, Zaire.

In Africa, female prostitutes represent a high risk group for HIV infection. In Kinshasa, Zaire, 101 (27%) out of 377 prostitutes were seropositive to HIV by ELISA and Western blot determination. Seropositivity was significantly associated with the number of lifetime partners with a median number of 600 partners, four seropositives and 338 for seronegative individuals (P = 0.02). Seropositivity was also significantly associated with a history of taking oral medications for the prevention of sexually transmitted diseases and/or pregnancy (odds ratio = 2.21, confidence interval = 1.2-4.2), and with the introduction of any product into the vagina for hygiene or other purposes (odds ratio = 2.3, confidence interval = 1.1-4.7). In addition, among 85 prostitutes reporting condom use by their sexual partners during the previous year, the use of condoms by 50% or more of partners was associated with a reduced risk of HIV seropositivity (P = 0.046). An increased risk of HIV seropositivity was not associated with fellatio, anal intercourse, or with any type of kissing. Twenty-nine per cent of prostitutes reported at least one symptom suggestive of HIV infection, and seropositivity was associated with weight loss, either with or without chronic diarrhea or pruritic dermatitis. These data confirm that African prostitutes are at high risk for HIV infection and that the number of lifetime sexual partners, and factors which interfere with the integrity of the vaginal or cervical mucosa, may be associated with an increased risk of HIV infection acquired through heterosexual contact.(ABSTRACT TRUNCATED AT 250 WORDS)

EVALUATION OF A CLINICAL CASE-DEFINITION OF ACQUIRED IMMUNODEFICIENCY SYNDROME IN AFRICA

A provisional clinical case-definition for acquired immunodeficiency syndrome (AIDS) developed by the World Health Organisation (WHO) for use in Africa was tested on 174 inpatients at Mama Yemo Hospital, Kinshasa, Zaire. In this hospital population with a 34% infection rate of human immunodeficiency virus (HIV), the clinical case-definition had a specificity of 90%, a sensitivity of 59%, and a predictive value of 74% for HIV seropositivity. These results support the use of the WHO clinical definition for AIDS in Africa. However, since HIV prevalence and disease expression vary, similar evaluations should be carried out in different regions.

RISK FACTORS FOR HUMAN IMMUNODEFICIENCY VIRUS SEROPOSITIVITY AMONG CHILDREN 1-24 MONTHS OLD IN KINSHASA, ZAIRE

A prevalence study of antibody to human immunodeficiency virus (HIV) was conducted in Kinshasa, Zaïre, among 258 children 2-24 months old who were in hospital, 191 children 1-20 months old who were attending a well-child clinic, and their mothers. 8% of the mothers of both groups of children were seropositive. Among children under 9 months old, 12 of 102 (12%) hospital inpatients and 11 of 136 (8%) clinic attenders were seropositive, while in the 9-24-month age group 20 of 156 (13%) hospital children and only 1 of 55 (2%) clinic children were seropositive (Fishers exact test, p = 0.01). 61% of the seropositive children had seropositive mothers, indicating a high rate of vertical transmission. Factors associated with seropositivity among hospital children with seronegative mothers included male sex, increased lifetime number of medical injections, and previous blood transfusion or hospital admission. Among children who had not previously been transfused or admitted to hospital the seropositives had received more medical injections than the seronegatives (median 34.5 versus 14.5; Wilcoxon rank sum test, p = 0.006). HIV infection accounted for or complicated a substantial proportion of hospital paediatric admissions. Public health measures are urgently required to prevent parenteral and vertical transmission of HIV to infants and young children in Kinshasa.

Recombinant viruses and early global HIV-1 epidemic.

HIV strains from Zaire indicate the HIV epidemic in Kinshasa was mature by the mid-1980s.

Vitamin A levels and mortality among hospitalized measles patients, Kinshasa, Zaire

Treatment with high dose vitamin A has recently been recommended for children with measles in communities where vitamin A deficiency is a recognized problem. However, the relationship between vitamin A and measles mortality has not been clearly established. We studied serum vitamin A levels in 283 children less than or equal to 5 years of age admitted to Mama Yemo and Kalembe Lembe Hospitals in Kinshasa, Zaire, between January and March, 1987. Vitamin A levels were determined by high performance liquid chromatography. Vitamin A levels ranged from less than 5 to 63 micrograms/dl (median, 8). The overall case-fatality rate was 26 per cent. On univariate analysis, age less than 24 months, pneumonia on admission, lymphopenia (less than 2000/mm3), and lower vitamin A levels were associated with death during hospitalization. In a multivariate logistic regression model, a vitamin A level less than 5 micrograms/dl was associated with fatal outcome for children younger than 24 months old (relative risk = 2.9, 95 per cent CI 1.3, 6.8), but not for older children. Further studies are needed to determine whether low vitamin A levels predispose children to severe measles and the role of vitamin A supplements in the prevention of measles mortality.

Knowledge, attitudes and beliefs about HIV infection and AIDS among healthy factory workers and their wives, Kinshasa, Zaire

As a first step in designing an AIDS prevention program at a large factory in Kinshasa, Zaire, we collected information on attitudes towards human immunodeficiency virus (HIV) infection and acquired immunodeficiency syndrome (AIDS) from factory foremen and their wives. Trained moderators conducted twelve focus group discussions (from November through December 1987) that addressed knowledge, attitudes and beliefs about HIV infection and AIDS. In general, participants were familiar with HIV infection and AIDS and considered these conditions leading health problems in Kinshasa. Although participants had a fairly accurate understanding of the causes of HIV infection, modes of transmission and preventive measures, many myths and misconceptions existed. Many participants did not believe that condom use would consistently prevent infection through sexual intercourse. Participants strongly favored the counseling of seropositive persons but showed less consensus about whether the spouse of a seropositive person should be notified of the partners test result. Participants predicted that couples in which one member is seropositive and the other is not would experience marital discord and friction with family, neighbors and co-workers. These findings were applied to the development of a counseling and educational program for seropositive factory employees and their spouses.

Evaluation of a rapid test for the detection of antibodies to human immunodeficiency virus type 1 and 2 in the setting of multiple transmitted viral subtypes

Rapid HIV testing is an appealing strategy in the approach to HIV diagnosis in developing countries. Concern has been raised about the use of these tests in the setting of multiply transmitted HIV subtypes. We sought to compare the OraQuickTM HIV-1/2 Test, a qualitative immunochromatographic test for the detection of antibodies to HIV-1 and HIV-2 using stored sera, with a conventional enzyme immunoassay (EIA)/Western blot (WB) algorithm. The study design used was a blinded retrospective study. Samples were collected on patients attending sexually transmitted disease clinics and tuberculosis clinics in Kinshasa, the Democratic Republic of Congo and included 72 known HIV seropositive and 131 known HIV seronegative subjects. All 72 known HIV seropositive samples were positive by OraQuick and all 131 known HIV seronegative samples were negative by OraQuick resulting in 100% sensitivity and specificity. We conclude that the OraQuick rapid HIV-1/2 test performs well in the setting of diverse HIV viral subtypes.