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P A Twumasi

Publications and source records attributed to P A Twumasi.

10 recordsLinked to original sources
PubMed1997

Induction of immunologic memory in Gambian children by vaccination in infancy with a group A plus group C meningococcal polysaccharide-protein conjugate vaccine.

Two hundred twenty-one Gambian children vaccinated previously with one, two, or three doses of a meningococcal conjugate vaccine or two doses of polysaccharide vaccine before the age of 6 months were revaccinated at the age of 18-24 months with either meningococcal polysaccharide, conjugate, or inactivated polio vaccines. Children who had previously received one, two, or three doses of conjugate vaccine had significantly (P < .001) higher anti-group C meningococcal antibody levels following revaccination than did children vaccinated with a polysaccharide vaccine for the first time. Children vaccinated previously with two doses of polysaccharide vaccine had a lower group C antibody response than did control children. Group A antibody responses following revaccination of children who had previously received polysaccharide or conjugate vaccine were not significantly higher than those in control children. Thus, immunologic memory was probably induced by the group C but not by the group A component of the conjugate vaccine.

Antibodies, Bacterial↗
PubMed1995

A trial of a group A plus group C meningococcal polysaccharide-protein conjugate vaccine in African infants.

The safety and immunogenicity of a group A plus group C meningococcal polysaccharide-CRM197 conjugate vaccine was evaluated in 304 8- to 10-week-old Gambian infants. Infants were immunized with one, two, or three doses of conjugate vaccine or with two doses of a meningococcal A plus C polysaccharide vaccine. The conjugate vaccine produced few systemic side effects, and local reactions were similar to those produced by the polysaccharide vaccine. Postvaccination group A meningococcal polysaccharide antibody levels, measured by ELISA, increased progressively after one, two, or three doses of conjugate vaccine. However, one dose of conjugate vaccine given at the age of 6 months induced a higher group C meningococcal antibody response than did two doses of conjugate vaccine given at 2 and 6 months. Two doses of conjugate vaccine induced higher levels of antibody than did two doses of polysaccharide vaccine. Thus, this new meningococcal conjugate vaccine proved to be safe and immunogenic.

Antibodies, Bacterial↗
PubMed1985

Local politicization of Primary Health Care as an instrument for development: a case study of community health workers in Zambia.

The integrated approach of the Primary Health Care Concept has obvious implications for development. In view of Zambia's commitment to Primary Health Care it is important to evaluate the effectiveness of present institutional frameworks and the problems that may arise in shifting towards community responsibility for the provision of health. It is often assumed that the Primary Health Care approach of working through the community should be free of serious implementation problems. However, experience from community participation projects in a wide variety fields carried out in many countries, including Zambia has shown that failure to account for local institutional arrangements and political interests has hindered success. This article presents the theoretical issues involved in community participation research, reviews relevant literature and presents a case study of a community health worker in Western Province, Zambia. The case study derives from an on-going UNICEF/Government of Zambia sponsored project which is monitoring and evaluating the impact of child health and nutrition services in rural areas. The study illustrates some of the problems encountered by a CHW because of clashes with local political interests. An alternative model is proposed which if implemented can help alleviate and/or avoid these types of conflicts.

Child↗