Two-dose measles vaccination schedules

As measles continues to exact a high toll on infant mortality, particularly in developing countries, optimal strategies for the control of the disease are under discussion. As part of this debate, the place of 2-dose measles immunization schedules is reviewed regarding their potential as a strategy to improve measles control. To date, WHO has not recommended the use of a 2-dose schedule. A number of industrialized countries have already adopted a 2-dose schedule, often choosing to administer measles vaccine in the same injection as mumps and rubella vaccines. However, at present not enough is known about such schedules in developing countries to make global recommendations. Further research should include randomized controlled trials of early 2-dose schedules to investigate both technical and epidemiological issues such as the effect of blunting immunity and the duration of antibody. Long-term safety should be determined through studies of adequate size. Programmes already using 2-dose schedules are encouraged to evaluate their impact on disease incidence, cost, vaccine usage, and effect on coverage. Until further evaluation is complete, a high and timely coverage with one dose of measles vaccine in all areas remains the first priority for all immunization programmes.

Evaluation of the home-based maternal record: a WHO collaborative study

Thirteen centres in eight countries (Egypt, India, Pakistan, Philippines, Senegal, Sri Lanka, Democratic Yemen and Zambia) participated in the WHO collaborative study to evaluate the home-based maternal record (HBMR). The evaluation showed that use of the HBMR had a favourable impact on utilization of health care services and continuity of the health care of women during their reproductive period. When adapted to local risk conditions, their cut-off points and the available resources, the HBMR succeeded in promoting self-care by mothers and their families and in enhancing the timely identification of at-risk cases that needed referral and special care. The introduction of the HBMR increased the diagnosis and referral of at-risk pregnant women and newborn infants, improved family planning and health education, led to an increase in tetanus toxoid immunization, and provided a means of collecting health information in the community. The HBMR was liked by mothers, community health workers and other health care personnel because, by using it, the mothers became more involved in looking after their own health and that of their babies. Apart from local adaptation of the HBMR, the training and involvement of health personnel (including those at the second and tertiary levels) from the start of the HBMR scheme influenced its success in promoting maternal and child health care. It also improved the collection of community-based data and the linking of referral networks.

Surveillance for the Expanded Programme on Immunization

Surveillance is the foundation of public health practice. This review examines the experience of surveillance in the Expanded Programme on Immunization (EPI). Surveillance systems include routine reporting, sentinel surveillance, and community-based reporting. Data from ongoing surveillance should be linked with those from supervision, health facility assessments, population surveys, and outbreak investigations to provide information for programme planning, implementation, evaluation, and modification. Evaluation of surveillance systems should assess the extent to which data are used for policy-making and programme improvement, and the simplicity, accuracy, completeness, timeliness and cost of the data. The surveillance of vaccine-preventable diseases has evolved as programmes mature, to monitor progress towards disease control targets. The establishment of goals to reduce measles cases by 90%, eliminate neonatal tetanus, and eradicate poliomyelitis has put increased emphasis on the need for effective disease surveillance. This opportunity should be taken to promote strengthening of national routine systems for disease surveillance, to make them effective instruments for prevention and control of diseases of public health importance.

Contraceptive vaccines

Three major approaches to contraceptive vaccine development are being pursued at the present time. The most advanced approach, which has already reached the stage of phase 2 clinical trials, involves the induction of immunity against human chorionic gonadotrophin (hCG). Vaccines are being engineered based on conjugates incorporating tetanus or diphtheria toxoid linked to a variety of hCG-based peptides centred on the beta-subunit of this molecule. Clinical trials have revealed that such preparations are capable of stimulating the production of anti-hCG antibodies. However, the long term consequences of such immunity in terms of safety or efficacy are, as yet, unknown. The alternative approaches to contraceptive vaccine development involve the induction of immunity against gamete-specific antigens found on the surface of the human spermatozoon or the zona pellucida. There is an abundance of experimental and clinical data to suggest that this approach is feasible although the biochemical characterization and synthesis of candidate antigens is still incomplete.

Childhood blindness: a new form for recording causes of visual loss in children

The new standardized form for recording the causes of visual loss in children is accompanied by coding instructions and by a database for statistical analysis. The aim is to record the causes of childhood visual loss, with an emphasis on preventable and treatable causes, so that appropriate control measures can be planned. With this standardized methodology, it will be possible to monitor the changing patterns of childhood blindness over a period of time in response to changes in health care services, specific interventions, and socioeconomic development.

Natural regulation of fertility

Natural methods play an important part in the overall control of world fertility. Lactational amenorrhoea makes a very large contribution to fertility control in developing countries and recent advances in our understanding of the biology of lactation and fertility have enabled guidelines to be prepared to help nursing mothers who wish to use the natural contraceptive effect of breastfeeding to space their families. Methods to identify more reliably the fertile phase of the menstrual cycle, possibly using home monitoring of hormone levels in the urine, would greatly increase the applicability of NFP methods. If used effectively, natural family planning can have a high effectiveness rate but all methods are extremely unforgiving of risk-taking in the fertile phase. More research is required to identify those factors which could serve to improve the efficacy of NFP methods.