Opsonic phagocytosis of Streptococcus pneumoniae by alveolar macrophages is not impaired in HIV-infected Malawian adults

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Opsonic phagocytosis of Streptococcus pneumoniae by alveolar macrophages is not impaired in human immunodeficiency virus infected Malawian adults

Streptococcus pneumoniae is a major cause of pneumonia, bacteremia, and meningitis, especially among adults infected with the human immunodeficiency virus (HIV). Alveolar macrophages (AMs) are critical components of cellular defense against bacterial infection and are both infected and affected by HIV. In this study, AMs obtained at bronchoscopy from 44 Malawian adults (24 HIV positive and 20 HIV negative) were exposed in vitro to opsonized S. pneumoniae and coagulase-negative staphylococci. AMs from HIV-positive and -negative volunteers showed no significant difference in binding to or internalization of either S. pneumoniae or coagulase-negative staphylococci. In HIV-positive subjects, the presence of detectable HIV in lung fluid was not associated with AM impairment. AMs from HIV-infected adults did not exhibit impaired pneumococcal phagocytosis in the assay used. This suggests that an alternative mechanism of susceptibility is operating in these individuals

Cross-Border Cholera Outbreaks in Sub-Saharan Africa, the Mystery behind the Silent Illness: What Needs to Be Done?

<div><p>Introduction</p><p>Cross-border cholera outbreaks are a major public health problem in Sub-Saharan Africa contributing to the high annual reported cholera cases and deaths. These outbreaks affect all categories of people and are challenging to prevent and control. This article describes lessons learnt during the cross-border cholera outbreak control in Eastern and Southern Africa sub-regions using the case of Uganda-DRC and Malawi-Mozambique borders and makes recommendations for future outbreak prevention and control.</p><p>Materials and Methods</p><p>We reviewed weekly surveillance data, outbreak response reports and documented experiences on the management of the most recent cross-border cholera outbreaks in Eastern and Southern Africa sub-regions, namely in Uganda and Malawi respectively. Uganda-Democratic Republic of Congo and Malawi-Mozambique borders were selected because the countries sharing these borders reported high cholera disease burden to WHO.</p><p>Results</p><p>A total of 603 cross-border cholera cases with 5 deaths were recorded in Malawi and Uganda in 2015. Uganda recorded 118 cases with 2 deaths and CFR of 1.7%. The under-fives and school going children were the most affected age groups contributing 24.2% and 36.4% of all patients seen along Malawi-Mozambique and Uganda-DRC borders, respectively. These outbreaks lasted for over 3 months and spread to new areas leading to 60 cases with 3 deaths, CRF of 5%, and 102 cases 0 deaths in Malawi and Uganda, respectively. Factors contributing to these outbreaks were: poor sanitation and hygiene, use of contaminated water, floods and rampant cross-border movements. The outbreak control efforts mainly involved unilateral measures implemented by only one of the affected countries.</p><p>Conclusions</p><p>Cross-border cholera outbreaks contribute to the high annual reported cholera burden in Sub-Saharan Africa yet they remain silent, marginalized and poorly identified by cholera actors (governments and international agencies). The under-fives and the school going children were the most affected age groups. To successfully prevent and control these outbreaks, guidelines and strategies should be reviewed to assign clear roles and responsibilities to cholera actors on collaboration, prevention, detection, monitoring and control of these epidemics.</p></div

Opsonic phagocytosis of Streptococcus pneumoniae by alveolar macrophages is not impaired in human immunodeficiency virus-infected Malawian adults

Streptococcus pneumoniae is a major cause of pneumonia, bacteremia, and meningitis, especially among adults infected with the human immunodeficiency virus (HIV). Alveolar macrophages (AMs) are critical components of cellular defense against bacterial infection and are both infected and affected by HIV. In this study, AMs obtained at bronchoscopy from 44 Malawian adults (24 HIV positive and 20 HIV negative) were exposed in vitro to opsonized S. pneumoniae and coagulase-negative staphylococci. AMs from HIV-positive and -negative volunteers showed no significant difference in binding to or internalization of either S. pneumoniae or coagulase-negative staphylococci. In HIV-positive subjects, the presence of detectable HIV in lung fluid was not associated with AM impairment. AMs from HIV-infected adults did not exhibit impaired pneumococcal phagocytosis in the assay used. This suggests that an alternative mechanism of susceptibility is operating in these individuals.</p

Cross-Border Cholera Outbreaks in Sub-Saharan Africa, the Mystery behind the Silent Illness: What Needs to Be Done? - Fig 2

<p>The map of Malawi (2a) and Uganda (2b) showing the location of the cholera affected districts and the distribution of the cholera cases in the study area.</p

The age distribution of cross-border cholera cases reported in Malawi and Uganda cholera treatment centres in 2015.

<p>The age distribution of cross-border cholera cases reported in Malawi and Uganda cholera treatment centres in 2015.</p

Reported cross-border cholera cases in Malawi and Uganda in 2015.

<p>Reported cross-border cholera cases in Malawi and Uganda in 2015.</p

The distribution of cholera cases by country of origin and sex.

<p>The distribution of cholera cases by country of origin and sex.</p

Laboratory results of the cross-border cholera cases seen in Uganda and Malawi in 2015.

<p>Laboratory results of the cross-border cholera cases seen in Uganda and Malawi in 2015.</p

Risk factors for the cross-border cholera outbreaks, interventions implemented and challenges experienced during response in Uganda and Malawi, 2015.

<p>Risk factors for the cross-border cholera outbreaks, interventions implemented and challenges experienced during response in Uganda and Malawi, 2015.</p