Asymptomatic Plasmodium falciparum carriage at the end of the dry season is associated with subsequent infection and clinical malaria in Eastern Gambia.

BACKGROUND: Chronic carriage of asymptomatic low-density Plasmodium falciparum parasitaemia in the dry season may support maintenance of acquired immunity that protects against clinical malaria. However, the relationship between chronic low-density infections and subsequent risk of clinical malaria episodes remains unclear. METHODS: In a 2-years study (December 2014 to December 2016) in eastern Gambia, nine cross-sectional surveys using molecular parasite detection were performed in the dry and wet season. During the 2016 malaria transmission season, passive case detection identified episodes of clinical malaria. RESULTS: Among the 5256 samples collected, 444 (8.4%) were positive for P. falciparum. A multivariate model identified village of residence, male sex, age ≥ 5 years old, anaemia, and fever as independent factors associated with P. falciparum parasite carriage. Infections did not cluster over time within the same households or recurred among neighbouring households. Asymptomatic parasite carriage at the end of dry season was associated with a higher risk of infection (Hazard Ratio, HR = 3.0, p < 0.0001) and clinical malaria (HR = 1.561, p = 0.057) during the following transmission season. Age and village of residence were additional predictors of infection and clinical malaria during the transmission season. CONCLUSION: Chronic parasite carriage during the dry season is associated with an increased risk of malaria infection and clinical malaria. It is unclear whether this is due to environmental exposure or to other factors.

Brief Report: Frailty in Aging People Living With HIV: A Matched Controlled Study.

BACKGROUND: We compared the prevalence of frailty among aging people living with HIV (PLHIV) with people without HIV from the ANS EP58 HAND 55-70 Study. METHODS: Cross-sectional multicentric study which consecutively included 200 PLHIV and 1000 people without HIV from the French national CONSTANCES cohort, matched on age, sex, and education level. PLHIV were aged 55-70 years, with a HIV viral load < 50 copies/mL and a lymphocyte T-CD4 level > 200 cells/µL for the last 24 and 12 months, respectively. We measured frailty (>2 items) and prefrailty (one or 2 items) using a proxy of the 5-item Fried score. Multivariate logistic regression was performed to assess the association between HIV and frailty/prefrailty, adjusting for demographic, social, behavioral, and comorbidity confounders. RESULTS: Outcome measures were available for 192 PLHIV and 822 people without HIV. The median age was 62 years, and 84.9% were men. Among PLHIV, the median CD4 cell count was 645.5 cells/µL. Prevalence of frailty/prefrailty was 5.73%/57.3% in PLHIV vs. 1.73%/52.2% in people without HIV, respectively. HIV was associated with prefrailty/frailty [odds ratio = 1.89; 95% confidence interval = 1.37 to 2.61), but after adjusting for social and behavioral factors and comorbidities, HIV was not significantly associated with prefrailty/frailty (odds ratio = 1.24; 95% confidence interval: = 0.84 to 1.81). In PLHIV only, frailty/prefrailty was associated with depressive symptomatology, kidney disease, and time since HIV infection. CONCLUSIONS: Prevalence of frailty is increased in aging PLHIV with well-controlled HIV disease, but other factors than HIV are predominant, particularly depression and comorbidities.