A new paradigm for international disease control: lessons learned from polio eradication in Southeast Asia

OBJECTIVES

This study evaluated the impact of international coordination on polio eradication in Southeast Asia.

METHODS

Active surveillance systems for acute flaccid paralysis were assessed. Analyses focused on surveillance proficiency and polio incidence.

RESULTS

Ten countries coordinated activities. Importations occurred and were rapidly contained in China and Myanmar. Countries that have been free of indigenous polio transmission for at least 3 years include Sri Lanka, Indonesia, Myanmar, and Thailand. In the remaining endemic countries--India, Nepal, and Bangladesh--poliovirus transmission has been substantially reduced; however, these countries still harbor the world's largest polio reservoir.

CONCLUSIONS

Unprecedented international coordination in Southeast Asia resulted in dramatic progress in polio eradication and serves as a paradigm for control of other infectious diseases such as malaria and tuberculosis.

When is a disease eradicable? 100 years of lessons learned

Since the 1915 launch of the first international eradication initiative targeting a human pathogen, much has been learned about the determinants of eradicability of an organism. The authors outline the first 4 eradication efforts, summarizing the lessons learned in terms of the 3 types of criteria for disease eradication programs: (1) biological and technical feasibility, (2) costs and benefits, and (3) societal and political considerations.

Surgical removal of non-age-related subfoveal choroidal neovascular membranes

PURPOSE

To assess anatomical and visual results following the surgical removal of non-age-related subfoveal choroidal neovascular membranes.

METHODS

A retrospective study was carried out of 31 consecutive patients undergoing vitrectomy, parafoveal retinotomy and removal of subfoveal choroidal neovascular membranes that were either idiopathic or associated with multifocal choroiditis, high myopia, trauma or angioid streaks.

RESULTS

Visual acuity improved or remained the same in 25 eyes (81%) after a mean follow-up of 10.1 months (range 3-37 months). visual acuity improved by more than 2 lines of Snellen acuity in 5 eyes (16%) and decreased by more than 2 lines in 2 eyes (6%). There was no significant association between the final visual outcome and length of symptoms prior to surgery or pre-operative visual acuity. Atrophy of the retinal pigment epithelium and older age were associated with poor outcome. Membranes recurred in 11 eyes (35%), and eyes with subfoveal blood prior to surgery were more likely to have recurrent membranes.

CONCLUSIONS

The results of surgical removal of non-age-related subfoveal neovascular membranes have been encouraging, but further studies of long-term outcome and of the natural history of individual conditions are required.

Current status of the global eradication of poliomyelitis

Substantial progress towards the global eradication of poliomyelitis by the year 2000 has been achieved since May 1988 when WHO Member States adopted this goal at the Forty-first World Health Assembly. Virtually all polio-endemic countries have begun to implement the WHO-recommended strategies to eradicate polio and it is expected that, by the end of 1997, all endemic countries in the world will have conducted full National Immunization Days (NID), providing supplemental oral polio vaccine (OPV) to nearly two-thirds of all children < 5 years. In contrast, although globally acute flaccid paralysis (AFP) surveillance was being conducted in 126 (86%) of 146 countries where polio is or recently was endemic, surveillance remains incomplete and untimely. A global network of polio laboratories, capable of detecting wild poliovirus when and where it occurs, has been developed. Furthermore, in countries where polio virus circulation has been limited to focal areas, and surveillance is adequate, mopping-up campaigns are being conducted to eliminate the final chains of transmission. The process for certification of polio eradication has been established in each WHO region as well as at the global level. The impact of the eradication initiative is evident, with an 88% decrease in the number of reported cases globally since 1988. In order to achieve the goal of eradication, the rapid development of complete and timely AFP surveillance and the continuation of effective NIDs constitute an urgent priority. This is of particular relevance in the remaining polio-endemic countries, especially in those that are affected by war or politically isolated and are important remaining reservoirs from where wild poliovirus continues to spread into bordering or even distant polio-free countries. External support will continue to be required by those countries and regions where the incidence of polio has reached low levels to ensure that final chains of poliovirus transmission are interrupted and to permit the eventual certification of eradication. The year 2000 objective for achieving poliomyelitis eradication remains a feasible target.

Disease eradication and health systems development

This article provides a framework for the design of future eradication programmes so that the greatest benefit accrues to health systems development from the implementation of such programmes. The framework focuses on weak and fragile health systems and assumes that eradication leads to the cessation of the intervention required to eradicate the disease. Five major components of health systems are identified and key elements which are of particular relevance to eradication initiatives are defined. The dearth of documentation which can provide "lessons learned" in this area is illustrated with a brief review of the literature. Opportunities and threats, which can be addressed during the design of eradication programmes, are described and a number of recommendations are outlined. It is emphasized that this framework pertains to eradication programmes but may be useful in attempts to coordinate vertical and horizontal disease control activities for maximum mutual benefits.

Polio outbreak in Albania, 1996

Between April and November 1996, a large outbreak of polio occurred in Albania, which had reported to be free of polio since 1985. Although Albania had not reported polio in that interval, the risk of introduction and circulation of wild poliovirus had in

Model-based estimates of the risk of human immunodeficiency virus and hepatitis B virus transmission through unsafe injections

BACKGROUND

Patient-to-patient transmission through contaminated medical equipment may be the principal route of nosocomial blood-borne infections globally. Quantifying cross infection risks could facilitate efforts to ensure safe injections in developing countries.

METHOD

A mathematical model was developed to evaluate the risk of cross infection due to unsafe injections. The model was applied to immunization programmes with a fixed number of injections and in which unsterile needle and syringe reuse rates were specified. Risk estimates were generated using a range of human immunodeficiency virus (HIV) and hepatitis B (HBV) prevalences.

RESULTS

The risk of cross infection is zero when properly sterilized equipment is used. With unsafe injections, the risk of cross infection with HBV is consistently higher than HIV for comparable levels of endemicity. A single reuse of each needle and syringe in areas with an HBeAg prevalence of 4% results in 980 cases of HBV/100,000 infants; reuse four times results in 3740 cases. When the HIV prevalence is 1% and the reuse rate is 4, 14 to 35 cases of HIV/100,000 women could occur. Contamination of multidose vaccine vials could considerably increase these estimates.

CONCLUSIONS

Neither HIV nor HBV transmission has been reported with injections administered through the Expanded Programme on Immunization. However, ample evidence exists that reuse of unsterile needles and syringes is common in developing countries. Ongoing efforts to ensure safe practices and improve injection technologies are required to protect these populations from both medical and traditional skin-piercing procedures.

Breast implants, rheumatoid arthritis, and connective tissue diseases in a clinical practice

This study was designed to assess the relationship between breast implants and certain rheumatologic diseases (rheumatoid arthritis and diffuse connective tissue diseases). The study base was a rheumatological practice in Atlanta, Georgia that started in 1982 and began computerizing its records in 1985. The computerized records through May 1992 included 4229 women patients, 150 with breast implants and 721 with a diagnosis of rheumatoid arthritis (RA) and/or one of the connective tissue diseases (CTDs). Of the 721 patients who had been diagnosed as having rheumatoid arthritis (RA) and/or one of the connective tissue diseases (CTDs), 392 had rheumatoid arthritis, 344 had connective tissue disease, 15 had both rheumatoid arthritis and a connective tissue disease, and 33 had more than one connective tissue disease. Of the patients with connective tissue disease, 179 had systemic lupus erythematosus, 64 had scleroderma, 49 had Sjögren's syndrome, 36 had dermatomyositis or polymyositis, and 49 had mixed connective tissue disease. Data were analyzed by univariate and multivariate techniques including logistic regression. Significant variables included age at first visit, income strata, and period of first visit. Analyses were performed for each clinical diagnosis, for all connective tissue diseases together (CTDs), and for those with rheumatoid arthritis and/or connective tissue disease (RA/CTD). Analyses were performed on the total data base and on the records of new patients (1986-1992). The adjusted odds ratio for breast implants among women who entered the practice in 1986-1992 and were diagnosed as having rheumatoid arthritis and/or one of the connective tissue diseases (RA/CTDs) was 0.45 (0.22-0.90), for those with rheumatoid arthritis was 0.61 (0.28-1.49), for those with any of these specific diffuse connective tissue diseases was 0.34 (0.11-1.06) compared to those without the disease. For systemic lupus erythematosus, the odds ratio of 0.24 (0.03-1.75) was based on a single case who had the disease 5 yr before the implant. For Sjögren's syndrome, the odds ratio was 1.67 (0.39-7.13) based on two cases, one of whom had the disease 5 yr before the implant. The calculated odds ratios for scleroderma, dermatomyositis/polymyositis, and mixed connective tissue disease were zero since no cases were diagnosed among the patients with breast implants. This study found no evidence that women with breast implants are at an increased risk for having rheumatoid arthritis or other diffuse connective tissue disease.

Reducing the risk of unsafe injections in immunization programmes: financial and operational implications of various injection technologies

The unsafe use and disposal of injection equipment continues to put patients, health care workers, and the general community at risk of infections such as hepatitis B virus and human immunodeficiency virus. Although the potential for unsafe injection practices varies substantially with the type of equipment that is used, technology alone cannot totally eliminate the risk. A knowledge of the cost, practicality and, most importantly, the potential for misuse, is critical for selecting the most appropriate injection equipment for each immunization setting. Four types of injection equipment are currently available for administering vaccines: sterilizable needles and syringes; standard disposable needles and syringes; autodestruct needles and syringes; and jet injectors. In general, the cost per injection is lowest with sterilizable equipment and highest with autodestruct. However, only autodestruct syringes virtually eliminate the risk of unsafe injection practices. Owing to differences in cost and programme factors, in some settings it may be appropriate to use a combination of equipment. For example, autodestruct syringes may be used in areas where it is difficult to ensure adequate supervision, while in medium-sized, fixed-site clinics with safe injection practices, sterilizable equipment will be the most cost-effective.

A framework for the evaluation of vaccines for use in the expanded programme on immunization

Since 1974, the Expanded Programme on Immunization (EPI) has provided technical support for the immunization of the world's children and women of childbearing age. Today, the vast majority of vaccines administered to these groups are delivered through the immunization programmes that have been established in developing countries. As these national programmes share many characteristics, the global use of a new or improved vaccine could be largely dependent on its compatibility with the priorities, existing antigens and vaccine delivery system of this network. Consequently, a framework has been developed for the systematic evaluation of candidate vaccines for use in EPI.

Higher socioeconomic status is associated with slower progression of HIV infection independent of access to health care

In order to identify socioeconomic characteristics associated with slower progression of HIV infection, we conducted a nested case-control study within a cohort of 729 homosexual men. The study compared non-progressors (defined as subjects who, at a follow-up visit during the period October 1989-December 1990, had been HIV positive for at least 5 years, had a CD4 count > 0.5 x 10(9)/l, had a Karnofsky score of 100%, were at Centers for Disease Control (CDC) Stage III or less, and had never received zidovudine or prophylaxis against Pneumocystis carinii pneumonia) with rapid progressors (defined as those who had developed AIDS other than Kaposi's sarcoma within 6 years of seroconversion, or within 5 years of enrollment if already seropositive). Rapidly progressing subjects were matched to non-progressing subjects on the basis of date of enrollment if seroprevalent and date of seroconversion if seroincident. Socioeconomic data were taken from the questionnaire obtained at enrollment into the cohort during 1982-84. There were 41 subjects in each group. A significantly higher proportion of the non-progressors had annual incomes above $10,000, at enrollment (85 vs 62%; p = 0.019). Similarly, a greater proportion of the non-progressors were more likely to have finished secondary school (100 vs 84%; p = 0.020) than rapid progressors. A higher proportion of non-progressors reported employment in management and professional positions (35 vs 15%). The non-progressing group also had a significantly higher socioeconomic index based on self-reported occupation (45.1 vs 38.3; p = 0.035). The association with higher income persisted even after adjustment for baseline CD4 count and symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Splenic cyst carcinoma presenting in pregnancy

A case report of squamous cell carcinoma in an epidermoid cyst of the spleen is diagnosed in a pregnant female. Elaboration on the clinical, radiological, and pathological findings is presented to emphasize the distinguishing features of benign and malignant cysts.