Excess risk of subsequent infection in hospitalized children from a community cohort study in Cambodia and Madagascar.

BACKGROUND: Children in low- and middle-income countries are particularly vulnerable in the months following an initial health event (IHE), with increased risk of mortality caused mostly by infectious diseases. Due to exposure to a wide range of environmental stressors, hospitalization in itself might increase child vulnerability at discharge. The goal of this study was to disentangle the role of hospitalization on the risk of subsequent infection. METHODS: Data from a prospective, longitudinal, international, multicenter mother-and-child cohort were analysed. The main outcome assessed was the risk of subsequent infection within 3 months of initial care at hospital or primary healthcare facilities. First, risk factors for being hospitalized for the IHE (Step 1) and for having a subsequent infection (Step 2) were identified. Then, inpatients were matched with outpatients using propensity scores, considering the risk factors identified in Step 1. Finally, adjusted on the risk factors identified in Step 2, Cox regression models were performed on the matched data set to estimate the effect of hospitalization at the IHE on the risk of subsequent infection. RESULTS: Among the 1312 children presenting an IHE, 210 (16%) had a subsequent infection, mainly lower-respiratory infections. Although hospitalization did not increase the risk of subsequent diarrhoea or unspecified sepsis, inpatients were 1.7 (95% Confidence Intervals [1.0-2.8]) times more likely to develop a subsequent lower-respiratory infection than comparable outpatients. CONCLUSION: For the first time, our findings suggest that hospitalization might increase the risk of subsequent lower-respiratory infection adjusted on severity and symptoms at IHE. This highlights the need for robust longitudinal follow-up of at-risk children and the importance of investigating underlying mechanisms driving vulnerability to infection.

Lockdown impact on age-specific contact patterns and behaviours, France, April 2020.

BackgroundMany countries implemented national lockdowns to contain the rapid spread of SARS-CoV-2 and avoid overburdening healthcare capacity.AimWe aimed to quantify how the French lockdown impacted population mixing, contact patterns and behaviours.MethodsWe conducted an online survey using convenience sampling and collected information from participants aged 18 years and older between 10 April and 28 April 2020.ResultAmong the 42,036 survey participants, 72% normally worked outside their home, and of these, 68% changed to telework during lockdown and 17% reported being unemployed during lockdown. A decrease in public transport use was reported from 37% to 2%. Participants reported increased frequency of hand washing and changes in greeting behaviour. Wearing masks in public was generally limited. A total of 138,934 contacts were reported, with an average of 3.3 contacts per individual per day; 1.7 in the participants aged 65 years and older compared with 3.6 for younger age groups. This represented a 70% reduction compared with previous surveys, consistent with SARS-CoV2 transmission reduction measured during the lockdown. For those who maintained a professional activity outside home, the frequency of contacts at work dropped by 79%.ConclusionThe lockdown affected the population's behaviour, work, risk perception and contact patterns. The frequency and heterogeneity of contacts, both of which are critical factors in determining how viruses spread, were affected. Such surveys are essential to evaluate the impact of lockdowns more accurately and anticipate epidemic dynamics in these conditions.