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H Jensen

Publications and source records attributed to H Jensen.

At least 19 recordsLinked to original sources

Routine vaccinations and child survival: follow up study in Guinea-Bissau, West Africa.

OBJECTIVE: To examine the association between routine childhood vaccinations and survival among infants in Guinea-Bissau. DESIGN: Follow up study. PARTICIPANTS: 15 351 women and their children born during 1990 and 1996. SETTING: Rural Guinea-Bissau. MAIN OUTCOME MEASURES: Infant mortality over six months (between age 0-6 months and 7-13 months for BCG, diphtheria, tetanus, and pertussis, and polio vaccines and between 7-13 months and 14-20 months for measles vaccine). RESULTS: Mortality was lower in the group vaccinated with any vaccine compared with those not vaccinated, the mortality ratio being 0.74 (95% confidence interval 0.53 to 1.03). After cluster, age, and other vaccines were adjusted for, BCG was associated with significantly lower mortality (0.55 (0.36 to 0.85)). However, recipients of one dose of diphtheria, tetanus, and pertussis or polio vaccines had higher mortality than children who had received none of these vaccines (1.84 (1.10 to 3.10) for diphtheria, tetanus, and pertussis). Recipients of measles vaccine had a mortality ratio of 0.48 (0.27 to 0.87). When deaths from measles were excluded from the analysis the mortality ratio was 0.51 (0.28 to 0.95). Estimates were unchanged by controls for background factors. CONCLUSIONS: These trends are unlikely to be explained exclusively by selection biases since different vaccines were associated with opposite tendencies. Measles and BCG vaccines may have beneficial effects in addition to protection against measles and tuberculosis.

Adolescent↗

Identification of ostrich and chicken cholecystokinin cDNA and intestinal peptides.

The cDNAs encoding the preprohormones of the regulatory peptides cholecystokinin (CCK) and the related gastrin have been identified in a number of vertebrate species. However, from birds only chicken preprogastrin is known. In the present study preproCCK cDNA was identified in two species of birds, ostrich and chicken. In addition, the molecular forms of the bioactive peptides expressed in the small intestine were characterized. Both preproCCKs contain mono basic processing sites for the production of CCK-70 and -8 as seen in turtle and bullfrog. However, compared to these species an unusually large proportion was processed to the small forms CCK-7 and -8 and only minute amounts to larger forms. The encoded preprohormones are very similar to each other and to turtle CCK. Furthermore, they also show a high degree of similarity to the CCKs identified in more distant vertebrates. This confirms that CCK is highly conserved among vertebrates while the structure of gastrin, the other member of the CCK/gastrin family, is considerably more variable.

Amino Acid Sequence↗

Comparison of human papillomavirus genotypes in archival cervical cancer specimens from Alaska natives, Greenland natives and Danish Caucasians.

Archival, formalin-fixed, paraffin-embedded cervical cancer specimens from 53 Alaska natives, 32 Greenland natives and 34 Danish Caucasians were analyzed for human papillomavirus (HPV) genotypes 16, 18, 31, 33, 35 and 45 and unidentified genotypes (HPV X) using PCR. The specimens were from the time period 1980-1989. No significant differences were observed in the overall HPV detection rates among cases from Alaska (98.1%), Greenland (84.4%) and Denmark (85.3%). HPV genotype 16 was the most prevalent type: 78.8% in Alaska natives, 96.3% in Greenland natives and 82.8% in Danish Caucasians. A prevalence of 21.2% HPV 31 and 30.8% HPV 33 was found in Alaska natives, of which most were coinfections with HPV 16. Only 3.7% HPV 31 and 3.7% HPV 33 were found in Greenland natives and no HPV 31 and 6.9% HPV 33 were found in Danish Caucasians. HPV 18 was only detected in Alaska natives and HPV 35 and 45 were not detected in any of the three populations. Infections with multiple genotypes were prevalent in Alaskan (36.5%) but not in Greenland natives (3. 7%) and Danish Caucasians (6.9%). The Eskimo subgroup of the Alaska native population has a significantly higher prevalence of HPV genotypes 31 and 33 associated with mixed infections in invasive cancer than the two other native subgroups (P = 0.04) and Greenland and Danish populations, reflecting genotype distributions in dysplasia and normal cervical cytology. The reason for HPV genotype diversity, although unknown, may be relevant to the current development of HPV vaccines.

Adolescent↗

Early BCG vaccination and reduction in atopy in Guinea-Bissau.

BACKGROUND: It has been proposed that certain viral and bacterial infections in early childhood may prevent allergic sensitization, by inducing Th1-type immune responses. This has led to speculation that mycobacterial vaccines might, through their Th1-stimulating properties, also protect against atopy. OBJECTIVE: To investigate whether the prevalence of atopy is lower in children who have been vaccinated with BCG in infancy than in children who have not been vaccinated. METHODS: We measured skin test reactivity to three allergens (Dermatophagoides pteronyssinus, D. farinae and cockroach) in 400 children, aged 3-14 years, as part of a follow-up study to examine the immune sequelae of measles in an urban area of Bissau, the capital of Guinea-Bissau in west Africa. Information on childhood vaccinations, including BCG in infancy, was available from child records. Of these children, 271 had been vaccinated with BCG (according to records) and 53 had not been vaccinated (no record and no BCG scar). Atopy was defined in two ways, according to the presence of any allergen reaction > or = 2 mm and any reaction > or = 3 mm. RESULTS: Of the children who had received BCG vaccine, 57 (21%) were atopic (any reaction > or = 2 mm), compared with 21 (40%) of the unvaccinated children [odds ratio, after controlling for potential confounding factors, 0.19 (95% CI 0.06-0.59)]. When atopy was defined using the 3-mm criterion, the reduction in atopy associated with BCG was greater the earlier the age at vaccination, and the largest reduction was seen in children vaccinated in the first week of life. CONCLUSION: BCG vaccination given early in infancy may prevent the development of atopy in African children.

Adolescent↗

Protection from cholera by adding lime juice to food - results from community and laboratory studies in Guinea-Bissau, West Africa.

Epidemiological studies have shown that food plays an important role in the transmission of Vibrio cholerae, and different foods have been incriminated in many epidemic outbreaks of cholera. Storing contaminated meals at ambient temperatures allows growth of V. cholerae. Some ingredients such as lime juice may inhibit the survival of V. cholerae in foods. During an epidemic caused by V. cholerae O1 in Guinea-Bissau in 1996, a case control study was conducted in the capital Bissau, the main affected region with an attack rate of 7.4%. Cases were hospitalized patients and controls were matched for area, gender and age. Lime juice in the sauce eaten with rice gave a strong protective effect (odds ratio [OR] = 0.31, 95% confidence interval [CI] = 0.17-0.56), and tomato sauce was also protective (OR = 0.36, 95% CI = 0.24-0.54). On the other hand, use of a bucket for storage of water in the house was associated with increased risk (OR = 4.4, CI = 2.21-8.74). Laboratory experiments to elucidate the inhibitory effect of different concentrations of lime juice on survival of V. cholerae in meals showed that V. cholerae thrives in rice with peanut sauce, but lime juice inhibited its growth. Since lime juice is a common ingredient of sauces, its use should be further encouraged to prevent foodborne transmission in the household during cholera outbreaks.

Adolescent↗

Risk factors for HIV-2 seropositivity among older people in Guinea-Bissau. A search for the early history of HIV-2 infection.

Because the seroprevalence of HIV-2 has been shown to be high in older age groups, we conducted a survey of all persons aged 50 years or over in two districts in Bissau, investigating the presence of HIV antibodies and possible risk factors for HIV infection with a particular emphasis on age, the impact of the war of independence (1963-74), traditional marital and extramarital sex patterns, blood contact and contact with monkeys. In 670 participants, the HIV-2 prevalence was 14.3%; 16.1% in women and 12.3% in men. The HIV-1 prevalence was only 0.5% (3/670). The HIV-2 prevalence peaked for men in the 60-69 years age group, and for women in the 50-59 years age group, declining markedly in the following age group for both men and women (OR = 0.09 (0.01-0.51), OR = 0.37 (0.15-0.82), respectively). This pattern could be due to differential mortality for HIV-2 infected individuals or to a cohort effect for a generation who were sexually active at the time of the war of independence in the 1960s and early 1970s in Bissau. Supporting the link with the colonial army, women who had had sex with a white man had a higher seroprevalence (OR = 3.63 (1.12-11.24)). The ethnic group indigenous to Bissau city had a much lower prevalence, but demographic and cultural risk factors such as marital status, religion, education and having lived outside Bissau were not associated with HIV-2. In the multivariate analyses for women, variables related to extramarital sex or prostitution (having sex with a white man, having lived in Senegal, not living with husband, and not marrying first sexual partner) were associated with higher risk. For men, previous spouses who had died or had divorced were associated with higher prevalence. Having married the first sexual partner was protective against HIV-2 infection for both men (OR = 0.29 (0.09-0.76)) and women (OR = 0.19 (0.04-1.00)). Hospitalizations, possibly due to transfusions, tended to be associated with higher risk, but only for women (OR = 1.83 (0.97-3.48)). The focus of the HIV-2 epidemic in Guinea-Bissau is likely to be endogenous, and the war of independence and the colonial army with its associated prostitution may have played an important part in propagating the virus.

Aged↗

Interventions during labor in relation to height in obese women.

The aim of the study was to investigate, whether height is a predictor of interventions during labor in obese women. Therefore the relationship between height and interventions during labor was investigated in 661 obese women delivering a single child in vertex presentation. Diabetic mothers were excluded. As a result there was a trend towards more medical inductions in tall women, but without reaching statistical significance. No other differences were found. We conclude, that short stature is not a major predictor of interventions during labor in Danish, obese women.

Body Height↗

Three-year follow-up of patients with pulmonary tuberculosis in Guinea-Bissau, West Africa.

SETTING: Raoul Follereau Hospital, Bissau, Guinea-Bissau. OBJECTIVE: To study the long-term outcome of patients with bacteriologically verified tuberculosis (TB), with or without human immunodeficiency virus (HIV) co-infection. DESIGN: Sputum samples were collected from all patients referred to the hospital with clinical symptoms of pulmonary tuberculosis. Direct microscopy and culture was performed at the Health Laboratory. Patients with a culture positive for Mycobacterium tuberculosis were followed for 3 years, and underlying factors were analysed regarding the outcome of treatment. A group of sex and age-matched HIV-negative individuals was used as controls. RESULTS: Of 206 bacteriologically verified pulmonary TB patients, 168 were followed up. Antibodies to HIV-2 were found in 33 patients (19.6%); eight patients (4.8%) had antibodies to HIV-1 or showed dual reactivity. Of 149 patients discharged to follow ambulatory treatment, the survival rate of HIV-2-positive patients was 42.3% (11/26) and for HIV-negative patients it was 81.9% (95/116). The difference in survival between HIV-2-positive and HIV-negative patients was highly significant (P < 0.00001). HIV-negative TB patients had a significantly higher mortality than their controls (mortality ratio 3.75, 95% confidence interval 1.58-8.90). Most patients who survived, regardless of HIV status, also became free from symptoms compatible wtih pulmonary TB. CONCLUSION: Although the mortality rate among HIV-positive TB patients was very much higher than among HIV-negative patients, there are weighty arguments for active contact tracing and effective treatment of all TB patients.

AIDS-Related Opportunistic Infections↗

Nutritional status and mortality of refugee and resident children in a non-camp setting during conflict: follow up study in Guinea-Bissau.

OBJECTIVE: To study the effects on children of humanitarian aid agencies restricting help to refugee families (internally displaced people). DESIGN: Follow up study of 3 months. SETTING: Prabis peninsular outside Bissau, the capital of Guinea-Bissau, which has functioned as a refugee area for internally displaced people in the ongoing war, and the study area of the Bandim health project in Bissau. PARTICIPANTS: 422 children aged 9-23 months in 30 clusters. MAIN OUTCOME MEASURES: Mid-upper arm circumference and survival in relation to residence status. RESULTS: During the refugee situation all children deteriorated nutritionally, and mortality was high (3.0% in a 6 week period). Rice consumption was higher in families resident in Prabis than in refugees from Bissau but there was no difference in food expenditure. Nutritional status, measured by mid- upper arm circumference, was not associated with rice consumption levels in the family, and the decline in circumference was significantly worse for resident than for refugee children; the mid-upper arm circumference of refugee children increased faster than that of resident children. For resident children, mortality was 4.5 times higher (95% confidence interval 1.1 to 30.0) than for refugee children. Mortality for both resident and refugee children was 7.2 times higher (1.3 to 133.9) during the refugee's stay in Prabis compared with the period after the departure of the refugees. CONCLUSION: In a non-camp setting, residents may be more malnourished and have higher mortality than refugees. Major improvements in nutritional status and a reduction in mortality occurred in resident and refugee children as soon as refugees returned home despite the fact that there was no improvement in food availability.

Eating↗

Effect of subclinical infection on maintaining immunity against measles in vaccinated children in West Africa.

BACKGROUND: Despite a high coverage with measles vaccines in parts of west Africa, epidemics of measles occur with reduced severity in an increasing proportion of older children who have been vaccinated. We examined the effect of exposure to natural measles on immunity in vaccinated children. METHODS: Our study was carried out in 1992 during an epidemic of measles in Niakhar, a rural area of Senegal with about 27,000 inhabitants who mostly live in compounds that include several households; within each household people live in different huts. Vaccine coverage in Niakhar was 81% at the time of our study. We measured haemagglutinin-inhibiting antibody at exposure and twice thereafter (after 4-5 weeks and at 6 months) in 36 vaccinated and 87 unvaccinated children. The frequency of measles and subclinical measles--defined as a four-fold or greater rise in antibody titre without clinical signs or symptoms--was related to intensity of exposure according to whether the index case was in the same hut, household, or compound. FINDINGS: Clinical measles occurred in 20 (56%) of 36 unvaccinated children and in one (1%) of 87 vaccinated children. Subclinical measles occurred in 39 (45%) of 86 vaccinated children who were exposed to measles and in four (25%) of 16 unvaccinated children. The frequency was inversely related to pre-exposure antibody concentration (p<0.001 for trend) and directly related to intensity of exposure (p=0.002 for trend). Antibody concentrations in subclinical cases increased on average by 45-fold and remained raised for at least 6 months. INTERPRETATION: Increased antibody titre after subclinical measles may be common in vaccinated children in West Africa where the intensity of exposure is high. As measles vaccination coverage increases, the circulation of wild measles will decrease, and vaccine-induced antibody is less likely to be boosted. Thus, new epidemics, albeit milder in form, may occur in vaccinated areas which should be recognised in campaigns to eradicate measles.

Adolescent↗

Effects of butter oil blends with increased concentrations of stearic, oleic and linolenic acid on blood lipids in young adults.

OBJECTIVE: The aim of this present project was to evaluate a more satisfactory effect on plasma lipoprotein profile of spreads based on dairy fat. DESIGN: This study was designed as a randomised cross-over experiment with a three-week treatment separated by a three-week wash-out period. Sixty five grams of the fat content of the habitual diets was replaced by either butter/grapeseed oil (90:10) (BG); butter oil and low erucic rapeseed oil (65:35) (BR) or butter blended in a 1:1 ratio with a interesterified mixture of rapeseed oil and fully hydrogenated rapeseed oil (70: 30) (BS). SUBJECTS: Thirteen healthy free-living young men (age 21-26 y) fulfilled the study. INTERVENTIONS: At the beginning and end of each diet period two venous blood samples were collected. Triacylglycerol and cholesterol concentrations in total plasma and VLDL, LDL, IDL and HDL fractions were measured, as were apo A-1 and apo B concentrations. Fatty acid composition of plasma phospholipids, plasma cholesterol ester and platelets was also determined. RESULTS: Significantly (P < 0.05) lower total and LDL-cholesterol concentrations were observed after the BR and BS period, compared to BG. The effect of BR and BS did not differ. BG and BR resulted in equal concentrations of HDL-C, but significantly higher than BS. Consequently, a significantly lower LDL-C/HDL-C ratio was seen after the BR treatment compared to BG and BS. Apo A-1 concentrations were not significantly different, but Apo B was significantly increased after BG. CONCLUSIONS: Partially replacing milk fat with rapeseed oil seems to yield a more healthy spread. Stearic acid had a HDL-C lowering effect compared to milk fat, but did not affect LDL-C significantly. The addition of stearic acid did not improve the plasma lipoprotein profile for young men with low cholesterol levels.

Adult↗

Increased prevalence of retrovirus infections among older women in Africa.

Recent studies of HIV-2 have suggested an increased incidence and prevalence among women older than 45 y compared with younger women. We therefore examined whether this phenomenon applied generally to all 3 major retroviruses, HIV-1, HIV-2 and HTLV-I, among women in Africa. We conducted a MedLine search from 1987 to 1997, using the keywords Africa and HIV-1, HIV-2 or HTLV, respectively. Community studies, national surveys and studies on professional cohorts were selected. Age groups > 45/50 y were compared with the age group with the lowest female/male prevalence ratio between 20 and 44 y of age. Thirty-one studies had sufficient data to be included. The female/male odds ratio (OR) for seropositivity was calculated for the old and the young age groups, respectively, providing the ratio of odds ratios: OR (old)/OR (young). Summary ratios for studies of all 3 retroviruses were estimated. In general we found a higher female/male prevalence ratio in the age group over 45/50 y than in the younger age group. For HIV-1 the odds ratio was 1.82 times [95% confidence interval (CI) 1.19-2.79] higher in the old age group than in the young group. For HIV-2 it was 1.97 [95% CI 0.95-4.08], and for HTLV-I it was 2.02 [95% CI 0.99-4.14] times higher. For all 3 viruses combined, the ratio was 1.88 [95% CI 1.36-2.61]. The few incidence studies of HIV-1 and HIV-2 indicated a similar tendency. Since differential mortality is unlikely to explain the pattern, the increase in the HIV-1, HIV-2 and HTLV-I female/male prevalence ratio suggests that older women may have increased exposure or susceptibility to all 3 retrovirus infections.

Adult↗

Increased long term mortality associated with rash after early measles vaccination in rural Senegal.

OBJECTIVES: To examine whether clinical symptoms, including rash, were more common after measles immunization compared with placebo and to study the association between postvaccination symptoms and later mortality. DESIGN: Examination of side effects in the 3 weeks after immunization in a trial of high titer and standard titer measles vaccines. PATIENTS: Two hundred twenty-four children randomly selected to be included in the surveillance for diarrhea, fever and rash. RESULTS: There was no difference in fever and diarrhea between recipients of high titer vaccines and recipients of placebo. However, high titer recipients tended to have more measles-like rashes than placebo recipients [relative risk, 2.12 (range, 0.90 to 5.03)]. Among recipients of high titer vaccines, children who presented a rash had higher mortality in the following 5 to 7 years than those who did not develop rash [mortality rate ratio, 3.85 (range, 1.52 to 9.79)]. High titer recipients without a rash had the same mortality as children in the placebo group who were given standard doses of measles vaccine at 10 months of age [mortality rate, 0.76 (range, 0.35 to 1.62)]. CONCLUSIONS: These observations suggest that in this particular study, rash after high titer measles vaccine may identify children who received a particularly high dose of vaccine or children with more severe and persistent postvaccination immunosuppression. Whether high titer vaccine is more likely than standard titer measles vaccine to provoke such reaction is not known, given that we did not compare side effects after different titers of measles vaccine. Future trials of live measles vaccine should monitor the development of rash.

Cause of Death↗

Poor serologic responses five to seven years after immunization with high and standard titer measles vaccines.

BACKGROUND: Few data exist on the persistence of measles antibodies after vaccination of West African infants. Therefore we examined measles antibody titers 5 to 7 years after children in rural Senegal had received high titer Edmonston-Zagreb (EZ-HT), high titer Schwarz (SW-HT) or standard titer Schwarz (SW-STD) measles vaccines in infancy. METHODS: Children had received either high titer vaccines at 5 months of age or standard titer at 10 months of age. Finger prick blood samples were tested for measles antibody 5 to 7 years later by the hemagglutinin inhibition test. RESULTS: Persistence of antibody after high titer vaccines was poor with the result that 39 and 50% of the EZ-HT and the SW-HT groups had low titers of hemagglutinin inhibition measles antibodies (< or =125 mIU/ml). Nineteen percent of the children in the SW-STD group had low titers which is a lower prevalence than in the high titer groups [relative risk (95% confidence intervals), 0.05 (0.28 to 0.88) vs. EZ-HT; relative risk, 0.38 (0.22 to 0.66) vs. SW-HT]. Geometric mean (95% confidence interval) antibody titers in children with detectable values were 616 (435 to 871) in the EZ-HT, 1106 (616 to 1866) in the SW-HT and 1271 (871 to 1741) mIU/ml in the SW-STD groups, respectively. Multivariant regression analysis showed that mean titers were 2.00 (1.03 to 3.89) times higher for children with low prevaccination antibody titers (< or =125 mIU/ml) and 3.06 (1.90 to 4.94) times higher if blood was collected in the rainy season. INTERPRETATION: Given the rapid decline in antibody titers over a 5- to 6-year period in an area where measles vaccine coverage was high, it seems likely that multiple dose immunization schedules will be needed in the future to maintain protective antibody concentrations (>125 mIU/ml) in West Africa. The role of subclinical boosting by exposure to natural measles and the possible role of malaria, which increases immunoglobulin turnover, in influencing long term antibody persistence after vaccination deserve further investigation.

Antibodies, Viral↗

The influence of prepregnancy body mass index on labor complications.

BACKGROUND: To investigate the influence of Body Mass Index on the incidence of labor complications in a population of women with a normal pregnancy. MATERIAL AND METHODS: From a local database, information on maternal weight and height was extracted concerning 4258 women who had an uncomplicated pregnancy. After calculation and stratification with respect to Body Mass Index, this was retrospectively related to labor interventions and complications. RESULTS: High Body Mass Index was related to more oxytocin infusion and early amniotomy, but not to vacuum extraction or cesarean section. Primary inertia and, to a minor degree, cephalopelvic disproportion and secondary inertia were seen more often in women with high Body Mass Index. CONCLUSIONS: Overweight (25.0<=BMI<30.0) and obesity (BMI>=30.0) are only weak predictors of labor complications, given a normal pregnancy. However, the heavy use of labor augmentation indicates that obese women should not be recommended to give birth in an ABC-clinic or at home.

Body Mass Index↗

[Delivery of extremely large infants].

The purpose of this retrospective study was to find out if more effort should be applied to the diagnosis of extremely large infants, with a birth weight of 5,000 grams or more, and if elective caesarean section can be recommended. In the Department of Obstetrics, Herning Central Hospital, Denmark, 67 mothers delivered an infant with a birth weight of 5000 g or more over a ten year period. This index group was compared with a matched group with infants of normal weight. The result showed significantly more caesarean sections in the index group (24% versus 5%, p = 0.002). Shoulder dystocia and Duchenne-Erb's palsy were more frequent as well. Sixteen percent in the index group were admitted to the paediatric department, but the Apgar scores were not significantly lower. Except for one, all the infants showed complete recovery. In conclusion, elective caesarean section can not be generally recommended for an estimated birthweight exceeding 5,000 g, if a trained obstetrician is present at delivery.

Apgar Score↗

Acute and long-term changes in T-lymphocyte subsets in response to clinical and subclinical measles. A community study from rural Senegal.

To investigate the possibility of long-term suppression of T-lymphocyte subsets, we examined children exposed to measles at home during an epidemic in rural Senegal, at time of exposure and 1 and 6 months later. The measles case fatality ratio was 1%. Subclinical measles was common among vaccinated children exposed to measles (45%). Both clinical and subclinical cases of measles showed a significant rise in absolute CD4 count in the incubation period. In the prodromal phase and the first week after the rash, the lymphocyte percentage, the white blood cell count and the absolute CD4 cell numbers were significantly reduced. There was no persistent decrease of absolute CD4 or CD8 numbers at 1 or 6 months after exposure. Measles infection was followed by significant changes in the subset composition, both CD4 and CD8 percentages being significantly higher in the second month after measles than among non-seroresponders. These changes were more marked among girls, since they had significantly higher CD4 percentages and CD4/CD8 ratios than boys in the convalescence phase. In conclusion, measles infection is not associated with a long-term suppression of CD4+ or CD8+ T-lymphocytes.

Adolescent↗

Mortality among human immunodeficiency virus type 2-positive villagers in rural Guinea-Bissau is correlated with viral genotype.

We present the results of a 6-year study of 131 human immunodeficiency virus (HIV) type 2 (HIV-2)-infected individuals from a rural population in Guinea-Bissau. Proviral DNA sequences 1.3 kb in length were obtained from each individual and, together with clinical data, including proviral load and CD4 and CD8 levels, were used to assess whether viral genotype influences clinical outcome. With a phylogenetic model, a correlation was found between viral genotype and mortality; this correlation was not due to confounding factors, such as age-specific viral strains or cohabitation of patients. The data provide strong evidence for the involvement of viral genetic factors in determining HIV disease progression in vivo. The pattern of association found suggests that virulence factors are multiple and scattered throughout the HIV-2 genome and can be rapidly gained or lost by the virus through a combination of mutation and recombination. These findings may lead to the identification of viral determinants of HIV disease progression.

Adolescent↗