HIV decline in Zimbabwe due to reductions in risky sex? Evidence from a comprehensive epidemiological review

Background Recent data from antenatal clinic (ANC) surveillance and general population surveys suggest substantial declines in human immunodeficiency virus (HIV) prevalence in Zimbabwe. We assessed the contributions of rising mortality, falling HIV incidence and sexual behaviour change to the decline in HIV prevalence. Methods Comprehensive review and secondary analysis of national and local sources on trends in HIV prevalence, HIV incidence, mortality and sexual behaviour covering the period 1985-2007. Results HIV prevalence fell in Zimbabwe over the past decade (national estimates: from 29.3% in 1997 to 15.6% in 2007). National census and survey estimates, vital registration data from Harare and Bulawayo, and prospective local population survey data from eastern Zimbabwe showed substantial rises in mortality during the 1990s levelling off after 2000. Direct estimates of HIV incidence in male factory workers and women attending pre- and post-natal clinics, trends in HIV prevalence in 15-24-year-olds, and back-calculation estimates based on the vital registration data from Harare indicated that HIV incidence may have peaked in the early 1990s and fallen during the 1990s. Household survey data showed reductions in numbers reporting casual partners from the late 1990s and high condom use in non-regular partnerships between 1998 and 2007. Conclusions These findings provide the first convincing evidence of an HIV decline accelerated by changes in sexual behaviour in a southern African country. However, in 2007, one in every seven adults in Zimbabwe was still infected with a life-threatening virus and mortality rates remained at crisis leve

Impact of COVID-19 on immunocompromised populations during the Omicron era:insights from the observational population-based INFORM study

Background Immunocompromised individuals are not optimally protected by COVID-19 vaccines and potentially require additional preventive interventions to mitigate the risk of severe COVID-19. We aimed to characterise and describe the risk of severe COVID-19 across immunocompromised groups as the pandemic began to transition to an endemic phase. Methods COVID-19-related hospitalisations, intensive care unit (ICU) admissions, and deaths (01/01/2022-31/12/2022) were compared among different groups of immunocompromised individuals vs the general population, using a retrospective cohort design and electronic health data from a random 25% sample of the English population aged ≥12 years (Registration number: ISRCTN53375662). Findings Overall, immunocompromised individuals accounted for 3.9% of the study population, but 22% (4585/20,910) of COVID-19 hospitalisations, 28% (125/440) of COVID-19 ICU admissions, and 24% (1145/4810) of COVID-19 deaths in 2022. Restricting to those vaccinated with ≥3 doses of COVID-19 vaccine (∼84% of immunocompromised and 51% of the general population), all immunocompromised groups remained at increased risk of severe COVID-19 outcomes, with adjusted incidence rate ratios (aIRR) for hospitalisation ranging from 1.3 to 13.1. At highest risk for COVID-19 hospitalisation were individuals with: solid organ transplant (aIRR 13.1, 95% confidence interval [95% CI] 11.2–15.3), moderate to severe primary immunodeficiency (aIRR 9.7, 95% CI 6.3–14.9), stem cell transplant (aIRR 11.0, 95% CI 6.8–17.6), and recent treatment for haematological malignancy (aIRR 10.6, 95% CI 9.5–11.9). Results were similar for COVID-19 ICU admissions and deaths. Interpretation Immunocompromised individuals continue to be impacted disproportionately by COVID-19 and have an urgent need for additional preventive measures beyond current vaccination programmes. These data can help determine the immunocompromised groups for which targeted prevention strategies may have the highest impact. Funding This study was funded by AstraZeneca UK

The Impact of Monitoring HIV Patients Prior to Treatment in Resource-Poor Settings: Insights from Mathematical Modelling

Using a stochastic model based on data from Africa, Timothy Hallett and colleagues find that starting HIV treatment based on regular CD4 monitoring, rather than on symptoms, would substantially increase survival

The epidemiology and impact of vertically acquired HIV infections and the effect of PMTCT interventions in Zimbabwe

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Voluntary counselling and testing: uptake, impact on sexual behaviour, and HIV incidence in a rural Zimbabwean cohort.

OBJECTIVES: To examine the determinants of uptake of voluntary counselling and testing (VCT) services, to assess changes in sexual risk behaviour following VCT, and to compare HIV incidence amongst testers and non-testers. METHODS: Prospective population-based cohort study of adult men and women in the Manicaland province of eastern Zimbabwe. Demographic, socioeconomic, sexual behaviour and VCT utilization data were collected at baseline (1998-2000) and follow-up (3 years later). HIV status was determined by HIV-1 antibody detection. In addition to services provided by the government and non-governmental organizations, a mobile VCT clinic was available at study sites. RESULTS: Lifetime uptake of VCT increased from under 6% to 11% at follow-up. Age, increasing education and knowledge of HIV were associated with VCT uptake. Women who took a test were more likely to be HIV positive and to have greater HIV knowledge and fewer total lifetime partners. After controlling for demographic characteristics, sexual behaviour was not independently associated with VCT uptake. Women who tested positive reported increased consistent condom use in their regular partnerships. However, individuals who tested negative were more likely to adopt more risky behaviours in terms of numbers of partnerships in the last month, the last year and in concurrent partnerships. HIV incidence during follow-up did not differ between testers and non-testers. CONCLUSION: Motivation for VCT uptake was driven by knowledge and education rather than sexual risk. Increased sexual risk following receipt of a negative result may be a serious unintended consequence of VCT. It should be minimized with appropriate pre- and post-test counselling

Evolution of RAS testing over time: factors influencing mutation rates in metastatic colorectal cancer patients

Contains fulltext : 219102.pdf (publisher's version ) (Open Access

Measuring and correcting biased child mortality statistics in countries with generalized epidemics of HIV infection

OBJECTIVE: Under Millennium Development Goal 4, countries are required to reduce child mortality by two-thirds between 1990 and 2015. In countries with generalized epidemics of human immunodeficiency virus (HIV) infection, standard statistics based on fertility history may misrepresent progress towards this target owing to the correlation between deaths among mothers and early childhood deaths from acquired immunodeficiency syndrome. METHODS: To empirically estimate this bias, child mortality data and fertility history, including births to deceased women, were collected through prospective household surveys in eastern Zimbabwe during 1998-2005. A mathematical model was then used to investigate the determinants and temporal dynamics of the bias, first in Zimbabwe and then in other countries with different background mortality rates and HIV-related epidemic profiles. FINDINGS: According to the empirical data, standard cross-sectional survey statistics underestimated true infant and under-5 mortality by 6.7% and 9.8%, respectively. These estimates were in agreement with the output from the model, in which the bias varied according to the magnitude and stage of the epidemic of HIV infection and background mortality rates. The bias was greater the longer the period elapsed before the survey and in later stages of the epidemic. Bias could substantially distort the measured effect of interventions to reduce non-HIV-related mortality and of programmes to prevent mother-to-child transmission, especially when trends are based on data from a single survey. CONCLUSION: The correlation between the HIV-related deaths of mothers and their children can bias survey estimates of early child mortality. A mathematical model with a user-friendly interface is available to correct for this bias when measuring progress towards Millennium Development Goal 4 in countries with generalized epidemics of HIV infection

Evolution of RAS testing over time: factors influencing mutation rates in metastatic colorectal cancer patients

Aim: Correct identification of RAS gene variants is key for targeted treatment decisions in patients with metastatic colorectal cancer. Published RAS mutation rates differ and could be influenced by several factors including testing methods. This study aimed to describe the performance of laboratories to correctly identify RAS variants over time and to understand how RAS testing has evolved in Europe. Materials & methods: Misclassification and test failure rates were calculated and related to the used test methodology for 239 unique laboratories participating in external quality assessment for metastatic colorectal cancer between 2013 and 2018. In addition, 33 laboratories completed a survey aiming to obtain more details on their routine testing strategies, number of samples analyzed and RAS mutation rates between 2013 and 2017. Results: The mutation status was correctly analyzed in 96.1% (N = 5471) RAS and BRAF tests. A total of 4.6% (N = 2860) RAS tests included false-negative results. In 1.6% (N = 5562) RAS and BRAF tests, an analysis failure occurred. Misclassifications and technical failures both decreased between 2013 and 2018. The number of next-generation sequencing users increased from 6.9% (N = 130) in 2013 to 44.6% (N = 112) in 2018. Over time, more codons were included in the methodologies, yet 23.2% (N = 112) did not offer full RAS testing (exon 2, 3, 4) in 2018. Based on the survey the overall RAS mutation rate was estimated as 45.2% (N = 27,325). Conclusion: This is the largest observational study reporting RAS mutation rates to-date. There was no trend of RAS mutation rates over time despite having a clear shift to more sensitive tests and increased quality of testing.status: Published onlin