Complications following Bacille Calmette-Guérin Vaccination in Children under the Age of 18 Months: A Multi-center Study

Background: The BCG vaccine, used since 1921 to prevent tuberculosis (TB), considered the world's most widely used vaccine. This study aimed to investigate the frequency and the type of complications associated with Bacillus Calmette-Guérin (BCG) vaccination in Iranian children. Materials and Methods This cross-sectional study conducted for 6months among children aged up to 18 months who presented to primary health care centers in Tehran (under supervision of all three Medical Universities of Tehran) for their routine vaccinations. All children had received BCG vaccination at birth. We investigated the occurrence of BCG complications through history taking from the parents and physical examination by the study physician. Complications categorized into four major groups: local, regional, remote, and generalized and the rate of occurrence compared between the two genders. Results: Finally, 14,095 children enrolled during the study period; 574 patients (4%) had experienced at least one complication following BCG vaccination. The most common complications were local side effects observed in 304 children (2.1%); followed by lymph node involvement detected in 270 children (1.9%). Lymph node involvement was more common in males (

Vaccine-associated Paralytic Poliomyelitis in Immunodeficient Children, Iran, 1995–2008

To determine the prevalence of vaccine-associated paralytic poliomyelitis (VAPP) in immunodeficient infants, we reviewed all documented cases caused by immunodeficiency-associated vaccine-derived polioviruses in Iran from 1995 through 2008. Changing to an inactivated polio vaccine vaccination schedule and introduction of screening of neonates for immunodeficiencies could reduce the risk for VAPP infection

Seroprevalence of antibodies to measles and rubella eight months after a vaccination campaign in the southeast of Iran

Eight months after the mass immunization campaign of November 2015 against measles and rubella in the southeast of Iran, in order to evaluate the sero-immunity level of the people living in the mentioned region, a serosurvey study was performed. Using a multi-stage probability proportional to size cluster sampling, the sera of 1,056 participants, ranging from 15 months to 20 years old, were tested for measles and rubella IgG antibodies in the National Reference Laboratory at Tehran University of Medical Sciences, Tehran, Iran. The seroprevalence rates of antibodies against measles and rubella in the age groups below 16 years were respectively 98.4 and 93.2%. In the age group of 16 to 20 years, who was not the target of the mass immunization campaign, the said rates were respectively 91.7% and 87.4%. The herd immunity of the age groups below 16 years, who were the target of the campaign, is favourably high and reassuring both for measles and for rubella. Campaigns of supplementary vaccination play a substantial role for filling the gaps in the herd immunity

The Effect of Age Group under 15 Years on Cholera Morbidity during the Past 10 Years in Iran (1996-2005)

Objective: The study of the effect of age, especially children under 15 years, on cholera morbidity during a period of ten years (1996-2005) was carried out in Iran. There are no other studies on this topic in Iran and other countries. Methods: In this cross sectional study, we used cholera surveillance data collected in Center for Disease Control. All cholera cases were divided into two groups: under 15 years and above 15 years. Incidence rate of cholera per 100000 was calculated in total population and the two mentioned groups during 10 years. The relative risk of less than 15 year-olds group to above 15 year-olds was calculated with95 % CI for 10 years by EPI6 and SPSS software. Findings: The trend of cholera incidence during the past 10 years shows two epidemic peaks in 1998 and 2005 by the rate of 15.7 and 1.63 per 100000, respectively. During the year with no epidemic and the years between two peaks, the age group under 15 year-olds was more affected with significant relative risk. For example, in 2001 this rate was 4.53. So, we can consider this age group as a risk factor to cholera morbidity. The age group of above 15 year-olds was more affected to cholera during epidemic years (1998, 2005) and relative risk was less than one. So, the age was protective on cholera morbidity for children in these years. Conclusion: One of the most important causes of periodic cholera epidemics every 5-6 years is changing of herd immunity. During the years between two epidemics adults have sufficient immunity and children are more affected because of first exposure and less immunity. With reduced herd immunity epidemics occur. We recommend continuing and strengthening of cholera surveillance system for detection of epidemics and treatment of highly sensitive age groups

Survival analysis for predictive factors of delay vaccination in Iranian children

Background: Today, beside immunization coverage the age appropriate vaccination is another helpful index in public health. Evidences have shown that high immunization coverage rates do not necessarily imply age-appropriate vaccination status. The current study aimed to show the predictive factors of delayed vaccination by survival models. Methods: A historical cohort study conducted on 3610 children aged between 24 and 47 months who was living in the suburbs of five big cities of Iran. Time of delay in vaccination of first dose of mumps-measles-rubella (MMR) was calculated from date of vaccination minus age appropriate time according to vaccine card. Kaplan-Maier and Log rank tests were used for comparison the median of delay time. For controlling of confounding variables, multivariate cox model was used and hazard ratio with 95% confidence interval (95%) was reported. Results: The mean ± standard deviation and median interquartile range of delay time was 38.34 ± 73.1 and 16 (11-31) days in delayed group. The Log rank test showed that city of living, nationality, parents′ education, and birth order are related with prolonged delay time in MMR vaccination (P 0.05). Cox regression showed that city of living, mother education, and nationality are the most predictive factors of delay time duration in MMR vaccination. Conclusions: Delay time duration of vaccination increased by faring from capital to the east south. Moreover, concentration of foreign immigrants in big cities and low level of mother education are the most predictors of delayed vaccination. Educational intervention should focus on immigrants and mothers with low education level

Risk factors of delay proportional probability in diphtheria-tetanus-pertussis vaccination of Iranian children; Life table approach analysis

Despite success in expanded program immunization for an increase in vaccination coverage in the children of world, timeliness and schedule of vaccination remains as one of the challenges in public health. This study purposed to demonstrate the related factors of delayed diphtheria-tetanus-pertussis (DTP) vaccination using life table approach. A historical cohort study conducted in the poor areas of five large Iran cities. Totally, 3610 children with 24-47 months old age who had documented vaccination card were enrolled. Time of vaccination for the third dose of DTP vaccine was calculated. Life table survival was used to calculate the proportional probability of vaccination in each time. Wilcoxon test was used for the comparison proportional probability of delayed vaccination based on studies factors. The overall median delayed time for DTP3 was 38.52 days. The Wilcoxon test showed that city, nationality, education level of parents, birth order and being in rural areas are related to the high probability of delay time for DTP3 vaccination (P 0.05). Being away from the capital, a high concentration of immigrants in the city borders with a low socioeconomic class leads to prolonged delay in DTP vaccination time. Special attention to these areas is needed to increase the levels of parental knowledge and to facilitate access to the health services care

Sero-epidemiological evaluation of rubella immunity among pre-marriage women in Iran

Few studies have addressed the seroepidemiological profile of rubella among a representative population of young adult women. This study aims to determine the immunity and susceptibility rate against rubella in a representative population of women in reproductive age in Iran through serological evaluation. This cross-sectional study was conducted in 2012 on 804 pre-marriage women in Iran. Multi-stage random sampling was used for choosing study sample. Serologic test were used to assess subjects’ immunity to rubella and their titers of IgG antibody against rubella with ELISA method was measured. In total, 98.4% (95% CI: 97.5% −99.2%) of study participants were immune against rubella. Five women (0.6%) were in borderline category and 1% (8 women) was susceptible to rubella. The proportion of immune people in low and high incidence regions was 99.3% (95% CI: 97.8–99.9%), and 97.5% (95% CI: 96.4–98.5%), respectively (P = 0.05). Our data indicated that level of immunity to rubella in women of reproductive age in Iran is satisfactory. This finding indicates the achievement of Iran to the goal of high level of serum immunity against rubella among young women

Estimation of measles risk using the World Health Organization Measles Programmatic Risk Assessment Tool, Iran

Introduction: Based on the World Health Organization (WHO) reports the EMRO countries did not reached to eradication of measles at 2010. This study aimed to estimate the risk of measles outbreak in different districts of Iran to identify high-risk areas based on WHO measles programmatic risk assessment tool. Materials and methods: The WHO measles programmatic risk assessment tool was used to estimate the overall risk of measles in 31 providences and 322 districts of Iran at 2017. The measles risk was calculated by a function of four indicator scores including population immunity, surveillance quality, program performance, and threat assessment and the overall risk of measles for each districts calculated. Then, the tool assigned each district a risk category of low, medium, high, or very high according to the overall risk score. Results: Of the 322 districts in Iran, all districts were categorized as low risk and there was no very high risk, high risk and medium risk district in Iran. Twenty-six districts (7.4%) received to risk point higher than 20. Based on population immunity and program delivery performance indicators, all districts in Iarn were categorized as low risk and 92.86% of districts were in low risk category by surveillance quality indicator. Conclusion: The overall risk of measles profile was categorized as low risk and Iranian practices for measles elimination is very good in comparing other studies in this area. However, more attempts should be conducted to sustaining the surveillance quality indicators in all districts