The impact of introduction of the 10-valent pneumococcal conjugate vaccine on pneumococcal carriage in Nigeria.

Pneumococcal conjugate vaccines (PCVs) protect against invasive pneumococcal disease (IPD) among vaccinees. However, at population level, this protection is driven by indirect effects. PCVs prevent nasopharyngeal acquisition of vaccine-serotype (VT) pneumococci, reducing onward transmission. Each disease episode is preceded by infection from a carrier, so vaccine impacts on carriage provide a minimum estimate of disease reduction in settings lacking expensive IPD surveillance. We documented carriage prevalence and vaccine coverage in two settings in Nigeria annually (2016-2020) following PCV10 introduction in 2016. Among 4,684 rural participants, VT carriage prevalence fell from 21 to 12% as childhood (<5 years) vaccine coverage rose from 7 to 84%. Among 2,135 urban participants, VT carriage prevalence fell from 16 to 9% as uptake rose from 15 to 94%. Within these ranges, carriage prevalence declined with uptake. Increasing PCV10 coverage reduced pneumococcal infection at all ages, implying at least a comparable reduction in IPD.

Nasopharyngeal Pneumococcal Carriage in Nigeria: a two-site, population-based survey.

Changes in nasopharyngeal (NP) carriage of vaccine-type (VT) Streptococcus pneumoniae can be used to assess the effectiveness of a pneumococcal conjugate vaccine (PCV10). We conducted a baseline carriage survey in rural (Kumbotso, Kano) and urban (Pakoto, Ogun) Nigeria. In this cross-sectional study, we obtained data on demography, clinical history, risk factors, and took NP swabs for pneumococcal culture. We calculated crude and age-standardised carriage prevalence and used log-binomial regression to assess risk factors for carriage. Among children aged <5 years, 92% (95% CI: 88-95%) and 78% (73-82%), respectively, carried any pneumococcus and 48% and 50%, respectively, carried PCV10 serotypes. In Kumbotso, carriage prevalence was >40% across all ages. The age-standardized prevalence of pneumococcal carriage was 66% in Kumbotso and 40% in Pakoto. The most commonly identified serotypes were 19 F, 6 A and 23 F. Risk factors for carriage were young age, recent rhinorrhoea, cohabitation with ≥2 children aged <5 years, and sharing a bed with ≥2 persons. Pneumococcal carriage prevalence is high in this Nigerian population. Persisting prevalence of VT-carriage in older children and adults suggests that PCV10 introduction in children will not eliminate transmission of vaccine serotypes rapidly. High vaccine coverage will therefore be required to ensure full protection of children.

Community-based study of contraceptive behaviour in Nigeria.

A cross sectional, community-based, descriptive study among women of reproductive age group (15-49 years) in Nigeria to explore the possible reasons for contraceptive non-use despite reported high awareness was carried out. Data were obtained using a standard questionnaire instrument and applied on 2001 respondents. Contraceptive prevalence among sexually active respondents was 14.8% for all methods, 10.1% for modern methods and only 0.8% for emergency contraceptives. The most frequently stated reasons for non-use of contraceptives, among those who had never used any contraceptives but who did not want more children were: "did not think about it", "against religious belief" and "fear of side effects." Prior counseling significantly improved the continuation rate of contraception. Multivariate analysis showed that older, married and more educated women tended to use contraceptives more. Health-care providers should be trained to offer counseling services to all clients in general, and young, unmarried and uneducated women in particular in order to improve their acceptance of contraceptives.

Sources of contraceptive commodities for users in Nigeria.

BACKGROUND: Understanding the sources of contraceptive commodities is an important aspect of the delivery of family planning services and is required by planning programme managers for strategic planning purposes. Findings from the 2003 Nigeria Demographic and Health Survey have previously showed that the private sector was the most frequently reported source of contraceptive supply, providing contraception to two and a half times as many women as the public sector. We conducted a community-based study to examine further the sources of contraceptive commodity for users in Nigeria with a view to identifying their preferences for distribution centres. This information would be useful to improve commodity distribution and to build the necessary capacity for satisfactory delivery of contraceptives. METHODS AND FINDINGS: A multi-stage random sampling technique was used. A state was randomly selected to represent each of the four health zones in Nigeria. Two local government areas (LGAs) were then selected representing both urban and rural areas. Ten enumeration areas were subsequently selected from each LGA. Of the 2,001 respondents aged 15-49 years, 1,647 (82.3%) were sexually active, out of which 244 were found to be using contraceptive methods at the time of the study, giving a contraceptive prevalence of 14.8%. The commonest source of information on contraceptives was through friends (34%), followed by the radio (11.5%) and husbands (10.2%). Most respondents procured their contraceptives from chemist/patent medicine shops (19.7%), while only 0.8% obtained them from designated family planning clinics. The younger groups in this study (15-24 years), single people, Catholics, and Muslims, showed a greater preference for chemist/patent medicine shops for their sources of contraceptives. The older groups and married respondents, however, made use of government and private hospitals to obtain their contraceptives. CONCLUSION: Strategies to increase contraceptive use must take into consideration these identified sources of contraceptives with a view to enhancing the quality, quantity, and variety of methods available, and to building capacity for effective service delivery. There is also a need to encourage the establishment of adolescent-friendly clinics where young people can go for counselling and obtain contraceptives of their choice, including emergency contraceptive pills.