Epidemic diphtheria in the 1990s: Azerbaijan

Delivering infectious disease interventions to women and children in conflict settings: a systematic reviefw

BACKGROUND

Conflict has played a role in the large-scale deterioration of health systems in low-income and middle-income countries (LMICs) and increased risk of infections and outbreaks. This systematic review aimed to synthesise the literature on mechanisms of delivery for a range of infectious disease-related interventions provided to conflict-affected women, children and adolescents.

METHODS

We searched Medline, Embase, CINAHL and PsychINFO databases for literature published in English from January 1990 to March 2018. Eligible publications reported on conflict-affected neonates, children, adolescents or women in LMICs who received an infectious disease intervention. We extracted and synthesised information on delivery characteristics, including delivery site and personnel involved, as well as barriers and facilitators, and we tabulated reported intervention coverage and effectiveness data.

RESULTS

A majority of the 194 eligible publications reported on intervention delivery in sub-Saharan Africa. Vaccines for measles and polio were the most commonly reported interventions, followed by malaria treatment. Over two-thirds of reported interventions were delivered in camp settings for displaced families. The use of clinics as a delivery site was reported across all intervention types, but outreach and community-based delivery were also reported for many interventions. Key barriers to service delivery included restricted access to target populations; conversely, adopting social mobilisation strategies and collaborating with community figures were reported as facilitating intervention delivery. Few publications reported on intervention coverage, mostly reporting variable coverage for vaccines, and fewer reported on intervention effectiveness, mostly for malaria treatment regimens.

CONCLUSIONS

Despite an increased focus on health outcomes in humanitarian crises, our review highlights important gaps in the literature on intervention delivery among specific subpopulations and geographies. This indicates a need for more rigorous research and reporting on effective strategies for delivering infectious disease interventions in different conflict contexts.

PROSPERO REGISTRATION NUMBER

CRD42019125221.

Diphtheria

Diphtheria is a contagious upper respiratory illness that was a major cause of childhood mortality in the prevaccine era. In the early twentieth century, an effective toxoid vaccine was developed. Implementation of childhood vaccination virtually eliminated diphtheria from developed countries after the Second World War and implementation of the Expanded Program on Immunization in developing countries led to rapid declines in diphtheria globally in the 1980s. However, in the 1990s, a massive epidemic of diphtheria spread throughout the countries of the former Soviet Union. Unlike the prevaccine era, most cases of severe disease and deaths were reported among adults. Multiple factors contributed to the epidemic, including increased susceptibility among both adults and children; suboptimal socioeconomic conditions; high population movement; and delay in implementing appropriate control measures. Mass immunization was the key element in the epidemic control strategy developed and implemented in a well-coordinated response by an international public health coalition. This strategy focused on rapidly raising population immunity of both adults and children; the immunization of more than 140,000,000 adults and adolescents and millions of children successfully controlled the epidemic. While improved coverage of children in developing countries with diphtheria toxoid has led to progressive decreases in diphtheria; eradication is unlikely in the foreseeable future and gaps in immunity among adult population exist or are developing in many other countries. Routine childhood immunization with diphtheria toxoid is the key to controlling diphtheria while the role of routine adult reimmunization is less established; mass immunization will remain an important control measure for widespread diphtheria outbreaks.

Prognostic significance of electrocardiographic abnormalities in diphtheritic myocarditis after hospital discharge: a long-term follow-up study

OBJECTIVE

We aimed to investigate the long-term cardiac mortality and the relationship between cardiac mortality and electrocardiographic abnormalities in patients with diphtheritic myocarditis who survived after hospital discharge.

MATERIALS AND METHODS

Between 1991 and 1996, 32 patients (all males, mean age 21.00 +/- 3.77 years) surviving diphtheritic myocarditis were included in the study and they were followed up for an average of 16.3 months (range 10.3-26.8 months) after hospital discharge. Clinical evaluation, ECG, and echocardiography were performed on admission, daily while in hospital and at the time of discharge. ECG changes were permanent during the follow-up period. The causes of death of the patients during follow-up period were inferred from the death records of the patients and talking to the people witnessing cardiac arrest.

RESULTS

We observed that the patients with left bundle branch block (LBBB) and T wave inversion at hospital discharge had lower survival rates than that of the patients without these ECG changes in the long term. Although univariate Cox regression analysis identified LBBB (P = 0.001) and T wave inversion (P = 0.014) as the predictors of survival, only LBBB was an independent predictor of survival in multivariate Cox regression analysis. Adjusted hazard ratio was calculated as 13.67 for LBBB (P = 0.001; CI = 2.81-66.28).

CONCLUSION

Diphtheritic myocarditis does not only demonstrate a malignant clinical course during acute phase of the disease, but also during the long-term follow-up period, especially in patients with LBBB and T wave inversion. Besides, T wave inversion and LBBB can help us to predict survival rate of the patients in long term. Moreover, LBBB is an independent predictor of long-term survival in diphtheritic myocarditis.

Successful control of epidemic diphtheria in the states of the Former Union of Soviet Socialist Republics: lessons learned

Epidemic diphtheria reemerged in the Russian Federation in 1990 and spread to all Newly Independent States (NIS) and Baltic States by the end of 1994. Factors contributing to the epidemic included increased susceptibility of both children and adults, socioeconomic instability, population movement, deteriorating health infrastructure, initial shortages of vaccine, and delays in implementing control measures. In 1995, aggressive control strategies were implemented, and since then, all affected countries have reported decreases of diphtheria; however, continued efforts by national health authorities and international assistance are still needed. The legacy of this epidemic includes a reexamination of the global diphtheria control strategy, new laboratory techniques for diphtheria diagnosis and analysis, and a model for future public health emergencies in the successful collaboration of multiple international partners. The reemergence of diphtheria warns of an immediate threat of other epidemics in the NIS and Baltic States and a longer-term potential for the reemergence of vaccine-preventable diseases elsewhere. Continued investment in improved vaccines, control strategies, training, and laboratory techniques is needed.

Diphtheria surveillance and control in the Former Soviet Union and the Newly Independent States

The Newly Independent States (NIS) inherited a common approach to diphtheria control from the Soviet Union and maintained a centralized system of surveillance and control managed by Soviet-trained epidemiologists with a shared professional culture. This system had controlled a diphtheria resurgence in the 1980s. In response to the epidemic of the 1990s, NIS health authorities responded with a set of control measures based on the Soviet-era experience. These measures included intensified childhood vaccination, aggressive case investigation, widespread diphtheria screening in institutions, and vaccination of adults in high-risk occupation groups. These measures proved insufficient due to high levels of susceptibility among adults, excessive contraindications to childhood vaccination, and insufficient resources in many countries. After these initial delays in implementing effective measures in some countries, most of the NIS health authorities rapidly and successfully implemented mass immunization of the population against diphtheria once the strategy was adopted and sufficient vaccine was available.