Background: Tanzania has a high prevalence (7.17%) of chronic hepatitis B infection. Mother to Child transmission is very common, resulting in high rate of chronic infections. Currently, there is no screening program for HBV in pregnant women. This study investigated the prevalence and risk factors for chronic HBV infection in pregnant women in a tertiary hospital in Mwanza, Tanzania. Methods: Seven hundred and forty-three women attending antenatal care and/or delivering at the Bugando Medical Centre were enrolled. All answered a questionnaire on sociodemographic and other risk factors and were tested for HBsAg using a rapid test. In HBsAg positive mothers, maternal blood and umbilical cord blood samples collected after delivery were analyzed for serological (HBsAg, HBeAg and anti-HBe) and virologic (HBV-DNA viral load and genotype) markers. All their babies were vaccinated within 24 h of delivery. The children were followed up at 3 years of age. Data was analyzed using the Mann-Whitney U-test, independent sample T-test and logistic regression. Results: Of the 743 participants, 22 (3%) were positive for HBsAg, and 2 (9%) had detectable HBe-antigen. Low condom use was the only statistically significant risk factor for chronic HBV infection (OR = 3.514, 95%CI = 1.4–8.0). Of 14 maternal blood samples genotyped, 10 (71%) were genotype A and 4 (29%) were genotype D. HBV-DNA was detected in 21/22 samples, with a median of 241 IU/ml (range: 27.4–25.9 × 107 IU/ml). Five (33%) of 15 available cord blood samples were positive for HBsAg and 10 (67%) were negative. At follow-up, one child showed chronic HBV infection characteristics, one had anti-HBs level of 7 mIU/ml and 5/7(71%) had protective anti-HBs levels (> 10 mIU/ml). Conclusion: This cohort of pregnant women showed a lower-intermediate prevalence of HBV of 3%. In the 3 years follow-up only 1 out of 7 children showed evidence of chronic HBV infection. The child’s mother with high viral load (25.9 × 107 IU/ml), was positive for HBeAg with a high degree of sequence similarity suggesting vertical transmission. These results highlight a need for improved diagnosis and treatment of HBV infection in pregnant women in Tanzania, in order to prevent vertical transmission.
23 November 2021 in Journal of Antimicrobial Chemotherapy
More than 15 million people in sub-Saharan Africa receive ART. Treatment failure is common, but the role of HIV drug resistance in treatment failure is largely unknown because drug resistance testing is not routinely done. This study determined the prevalence and patterns of HIV drug resistance in patients with suspected virological failure. A single high viral load of >1000 viral RNA copies/mL of plasma at any point during ART was considered as suspected virological failure. HIV-1 RNA was extracted from plasma samples of these patients using the QIAamp Viral RNA kit. The protease and part of the RT regions of the HIV pol gene were characterized. Viral load was determined in 317 patients; 64 (20.2%) had suspected virological failure. We successfully genotyped 56 samples; 48 (85.7%) had at least one major resistance-associated mutation (RAM). Common mutations in RT were M184V (75%), T215Y (41.1%), K103N (39.3%), M41L (32.1%), D67DN (30.3%), G190A (28.6%) and A98G (26.8%). No RAMs were detected in ART regimens based on a ritonavir-boosted PI. The Tanzanian national guidelines define ‘virological failure’ as two consecutive viral load measurement results, at 3 month intervals, above the WHO threshold (1000 copies/mL). Here, we show that a single viral load above the WHO threshold is associated with high rates of RAMs. This suggests that a single high viral load measurement could be used to predict virological failure and avoid delays in switching patients from first-line to higher genetic barrier second-line regimens.
1 January 2021 in AIDS Research and Human Retroviruses
HIV-1 Integrase (IN) is a primary target for combination antiretroviral therapy (cART). Only a limited number of studies report on the emergence of resistance-associated mutations (RAMs) in Cameroon. We observed that (1.4%) of sequence from treatment naïve patients had Integrase strand transfer inhibitor (INSTI) RAMs. These mutations confer resistance to raltegravir (RAL) and elvitegravir (EVG). We also observed that 10.1% of the sequences have INSTI accessory RAMs. HIV-1 CRF02_AG was the predominant subtype (44.7.%) in this study analyses. The occurrence of INSTI RAMs among the sequences at baseline needs to be monitored carefully.
27 August 2024 in Journal of Global Antimicrobial Resistance
Background: Prospective data on the effectiveness of resistance testing in informing treatment decisions and outcomes in with first-line failure in these settings is limited. This study aimed to assess the virological impact of HIV drug-resistance testing in patients with virological failure in Tanzania. Methods: Participants were randomly assigned to either the control or the experimental group. In addition to the standard of care, patients in the experimental group had access to genotypic drug-resistance testing, information used during treatment change, and were followed up at six-and 12-months to determine virological suppression. Results: A total of 261 patients with a median age of 32 (14.7–44.7) years were enrolled. In the intention-to-treat analysis, at 6-months, suppression was achieved in 58 (42.3%; 95% CI, 34.1–50.1) experimental group patients versus 51 (41.1%; 95% CI, 32.5–49.8) control group patients, with a p-value of 0.4. At-12 months, suppression was achieved in 110 (80.3%; 95% CI, 73.6–87) experimental patients versus 99 (79.8%; 95% CI, 72.8–86.9) control patients, with a p-value of 0.5. In the per-protocol analysis, at 6-months, suppression was observed in 38.46% (95% CI, 27.6–49.3) experimental patients versus 38.6% (95% CI, 26.0–51.2) control patients, with a p-value of 0.5. At 12-months, suppression was observed in 79.49% (95% CI, 70.5–88.5) of experimental patients versus 75.44% (95% CI, 64.3–86.6) of control patients, with a p-value of 0.3. Conclusion: Conducting HIV drug-resistance testing, and switch to individualised second-line regimens did not significantly improve virological suppression in patients experiencing first-line ART failure in Tanzania.
The emergence and spread of HIV drug resistance mutations (DRMs) pose a threat to current and future treatment options. To inform policy, this review aimed to determine the magnitude and patterns of DRMs in patients on ART in Tanzania. A systematic literature search was conducted in MEDLINE through PubMed, Embase, and CINAHL up to December 2024. A total of 9685 HIV patients from 23 eligible studies were analyzed. The prevalence of virological failure in studies that used a threshold of >1000 and >400 copies/mL was 24.83% (95% CI: 17.85–32.53%) and 36.94% (95% CI: 24.79–50.00%), respectively. Major DRMs were observed at 87.61% (95% CI: 76.25–95.91%). A decrease in prevalence was observed in studies conducted from 2019, with a pooled prevalence of 62.15% (95% CI: 31.57–88.33%). The most frequently observed HIV-1 subtypes were subtype C at 36.20% (95% CI: 30.71–41.85%), A1 at 33.13% (95% CI: 28.23–38.20%), and subtype D at 16.00% (95% CI: 11.41–21.12%), while recombinant forms of the virus were observed at 13.29% (95% CI: 9.79–17.17%). The prevalence of DRMs against NRTIs and NNRTIs was significantly high, while that against INSTIs and PIs was low, supporting the continued use of PI- and INSTI-based regimens in Tanzania and the need for continued surveillance of DRMs.
Background: On 15 January 2024, the Ministry of Health (MOH) reported a notable outbreak of acute viral conjunctivitis in the city of Dar es Salaam. In this study we investigated the causative agent of acute conjunctivitis outbreak which occurred in Dar es Salaam between Jan 2024 and Feb 2024. Methodology: We conveniently collected a pair of eye swab samples from twenty-five patients presenting with symptoms of acute conjunctivitis at clinics in Dar es Salaam during the outbreak. One for bacterial culture and another for molecular detection. MacConkey and Blood agar were used to culture patient samples to identify possible bacterial causes. A Multiplex Real-time RT-PCR targeting Adenovirus, Metapneumovirus, Human Enterovirus and Parainfluenza. Positive samples with Ct value less than 30 for enterovirus were subjected to genomic sequencing by Illumina Miseq after library preparation and enrichment by Illumina’s Respiratory Pathogen ID/AMR enrichment panel kit as per manufacturer’s instructions (RPIP kit), followed by bioinformatics and phylogenetic analysis. Results: Out of 25 samples, nine samples were positive for human enterovirus by Real-time PCR. Of the nine positive samples four were sequenced and Coxsackievirus A24 variant, was identified as the most probable cause of the outbreak. Phylogenetic analysis showed that samples collected during the outbreak (28AO and 26HB) belong to a clade with Coxsackievirus A24 sequences from France Mayotte from a 2024 outbreak, also close to sequences from neighbouring East African countries (Uganda, Kenya) as well as South American countries (Brazil, Mexico, and French Guiana). Conclusion: This study demonstrated the utility of genomic epidemiology in identifying Coxsackievirus A24 as the pathogen responsible for the outbreak and its circulation within the East African region.