Background The Gambia introduced seven-valent pneumococcal conjugate vaccine (PCV7) in August 2009, followed by PCV13 in May, 2011, using a schedule of three primary doses without a booster dose or catch-up immunisation. We aimed to assess the long-term impact of PCV on disease incidence. MethodsWe did 10 years of population-based surveillance for invasive pneumococcal disease (IPD) and WHO defined radiological pneumonia with consolidation in rural Gambia. The surveillance population included all Basse Health and Demographic Surveillance System residents aged 2 months or older. Nurses screened all outpatients and inpatients at all health facilities using standardised criteria for referral. Clinicians then applied criteria for patient investigation. We defined IPD as a compatible illness with isolation of Streptococcus pneumoniae from a normally sterile site (cerebrospinal fluid, blood, or pleural fluid). We compared disease incidence between baseline (May 12, 2008-May 11, 2010) and post-vaccine years (2016-2017), in children aged 2 months to 14 years, adjusting for changes in case ascertainment over time.Findings We identified 22 728 patients for investigation and detected 342 cases of IPD and 2623 cases of radiological pneumonia. Among children aged 2-59 months, IPD incidence declined from 184 cases per 100 000 person-years to 38 cases per 100 000 person-years, an 80% reduction (95% CI 69-87). Non-pneumococcal bacteraemia incidence did not change significantly over time (incidence rate ratio 0•88; 95% CI, 0•64-1•21). We detected zero cases of vaccine-type IPD in the 2-11 month age group in 2016-17. Incidence of radiological pneumonia decreased by 33% (95% CI 24-40), from 10•5 to 7•0 per 1000 person-years in the 2-59 month age group, while pneumonia hospitalisations declined by 27% (95% CI 22-31). In the 5-14 year age group, IPD incidence declined by 69% (95% CI -28 to 91) and radiological pneumonia by 27% (95% CI -5 to 49).Interpretation Routine introduction of PCV13 substantially reduced the incidence of childhood IPD and pneumonia in rural Gambia, including elimination of vaccine-type IPD in infants. Other low-income countries can expect substantial impact from the introduction of PCV13 using a schedule of three primary doses.

B y the end of October 2020, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic had spread to 6 continents and caused >45 million coronavirus disease (COVID-19) cases and 1.1 million deaths (1). Despite having 15.6% of the worldwide population (2), by October 31, 2020, Africa had only 3.9% (1.76 million) of the world's COVID-19 cases and 3.6% (42,233) of deaths during the pandemic (1). Data suggest that the pandemic is evolving differently in sub-Saharan Africa compared with the rest of the world and that the outbreak started later (3).Of note, severe COVID-19 cases seem to occur less frequently in Africa than in the rest of the world (4). Several factors have been proposed to explain this. Age is likely a major factor because older persons are at higher risk for severe disease, but Africa has an extremely young population; >60% of persons are <25 years of age (5). However, variation of CO-VID-19 severity with age alone does not fully explain the observed differences (4). Clinical cases and deaths in Africa likely are underreported because systematic surveillance is limited and no systematic death registration exists; thus, the true SARS-CoV-2 burden probably is underestimated (4). Nevertheless, local health systems in Africa, which have a lower capacity to deal with COVID-19 patients than healthcare systems in high-resource settings, were not overwhelmed, even at the peak of the epidemic (6). Although potential

ObjectivesTo determine the causes of lobar pneumonia in rural Gambia.Design and settingPopulation-based pneumonia surveillance at seven peripheral health facilities and two regional hospitals in rural Gambia. 7-valent pneumococcal conjugate vaccine (PCV7) was introduced routinely in August 2009 and replaced by PCV13 from May 2011.MethodsProspective pneumonia surveillance was undertaken among all ages with referral of suspected pneumonia cases to the regional hospitals. Blood culture and chest radiographs were performed routinely while lung or pleural aspirates were collected from selected, clinically stable patients with pleural effusion on radiograph and/or large, dense, peripheral consolidation. We used conventional microbiology, and from 8 April 2011 to 17 July 2012, used a multiplex PCR assay on lung and pleural aspirates. We calculated proportions with pathogens, associations between coinfecting pathogens and PCV effectiveness.Participants2550 patients were admitted with clinical pneumonia; 741 with lobar pneumonia or pleural effusion. We performed 181 lung or pleural aspirates and multiplex PCR on 156 lung and 4 pleural aspirates.ResultsPathogens were detected in 116/160 specimens, the most common being Streptococcus pneumoniae(n=68), Staphylococcus aureus (n=26) and Haemophilus influenzae type b (n=11). Bacteria (n=97) were more common than viruses (n=49). Common viruses were bocavirus (n=11) and influenza (n=11). Coinfections were frequent (n=55). Moraxella catarrhalis was detected in eight patients and in every case there was coinfection with S. pneumoniae. The odds ratio of vaccine-type pneumococcal pneumonia in patients with two or three compared with zero doses of PCV was 0.17 (95% CI 0.06 to 0.51).ConclusionsLobar pneumonia in rural Gambia was caused primarily by bacteria, particularly S. pneumoniae and S. aureus. Coinfection was common and M. catarrhalis always coinfected with S. pneumoniae. PCV was highly efficacious against vaccine-type pneumococcal pneumonia.

Background Pneumonia aetiology generally relies on insensitive blood cultures or an assumption that organisms in the pharynx are causal. We determined the causes of lobar pneumonia in rural Gambia using lung aspiration. Methods Pneumonia surveillance was undertaken among all ages. Blood culture and chest radiographs were performed routinely while lung or pleural aspirates were collected from selected patients. 7-valent pneumococcal conjugate vaccine (PCV7) was introduced in August 2009 and replaced by PCV13 from May 2011. We used conventional microbiology, and from April 8, 2011 to July 17, 2012, utilized a multiplex PCR assay on lung aspirates. We calculated proportions with pathogens, associations between co-infecting pathogens, and PCV effectiveness. Results 2,550 patients were admitted with clinical pneumonia; 741 with lobar pneumonia or pleural effusion. We performed multiplex PCR on 156 lung and 4 pleural aspirates. Pathogens were detected in 116 specimens, Streptococcus pneumoniae (n=68), Staphylococcus aureus (n=26), and Haemophilus influenzae type b (n=11). Bacteria (n=97) were more common than viruses (n=49). Common viruses were bocavirus (n=11) and influenza (n=11). Co-infections were frequent (n=55). M. catarrhalis was detected in eight patients and in every case there was co-infection with S. pneumoniae. The odds ratio of vaccine-type pneumococcal pneumonia in patients with two or three compared to zero doses of PCV was 0.17 (95% CI 0.06, 0.51). Conclusions Lobar pneumonia in rural Gambia was caused primarily by bacteria, particularly S. pneumoniae and S. aureus. Co-infection was common and M. catarrhalis always co-infected with S. pneumoniae. PCV was highly efficacious against vaccine-type pneumococcal pneumonia.