Chicken pox is a highly contagious and a major infectious disease, especially for children population in the world. It is caused by the varicella-zoster virus (WHO, 2016). The virus particles are infectious and cell-free which are derived from skin lesions or the respiratory tract as well. The transmission occurs mainly through the respiratory droplets which contain the virus, which makes the disease extremely contagious, even before the appearance of the rash. The normal period of incubation for the virus is around 10-21 days after which the first symptoms start appearing. The initial symptoms include the appearance of rash on the skin- itchy, red spots followed by high fever as well. Later, these rashes turn into fluid-filled blisters and start covering the body. The patient is in the contagious stage from the first 1-2 days before the rash appears and until the lesions crust over, which is around 6 days post the appearance of the first rash (Ayoade et al., 2017). It mainly causes an infection in the body and sometimes remains dormant in the ganglia or dorsal roots and gets reactivated in the later part of life. It leads to a reduction in the cell-mediated immunity of the individual affected and causes a more complicated disease-herpes zoster or shingles later in life (Hobbelen et al., 2016).
Varicella is not included in the list of universally notifiable diseases, even though around 300-1200 cases for every 100,000 population have been reported from Europe (Wutzler et al., 2017). Even though, varicella is usually benign in children, very serious complications can develop because of it and it was reported in 2014 by the World Health Organization that approximately 4.2 million complicated cases were reported which led to hospitalisations and around 4200 deaths also occurred globally, every year (WHO, 2016). Even though, in 2014, the vaccine for the disease was recommended in 33 mostly high income countries, it was observed that many countries still did not routinely vaccinate for chicken pox (Gray, 2017). Some reasons cited for low adoption include the cost of implementing the schedule for only a mild childhood illness and the other being the change or shift in age group for the occurrence of disease – from children to an older age group and associated increased risk of occurrence of Herpes zoster a well (Wutzler et al., 2017). One of the nations most notably, not including the vaccine as a part of their immunization schedule is the United Kingdom. In this study, we examine the effectiveness of the varicella vaccine against chicken pox and whether UK should introduce the vaccine in its immunization schedule or not.
Evidence is suggestive of the fact that around three-quarters of the parents in the United Kingdom have reported the occurrence and beginning of chicken pox in their children by the time they reach the age of five (Amirthalingam & Ramsay 2016). Around 31,406 children between the age group of 0-9 years have been suffering from chicken pox , indicative of an incidence rate of around 3.52 per 100000 children in the country (Hobbelen et al., 2016). These statistics are indicative of the magnitude and scale of the health complication this situation poses and that how significant- a health issue it is, for the country. It requires closer attention by the respective stakeholders and efforts from them as well to address this issue in a significant manner.
Thus, it is difficult to prevent the incidence of the occurrence of chicken pox in the country. Hence, it is important to analyze if the vaccine should be introduced or not as a routine regimen for vaccination for the children in UK or not. This critical appraisal will serve as an effective piece of evidence for the policy makers and healthcare professionals and help provide guidance in terms of decision making about the inclusion and implementation of the varicella vaccine in the routine program.
The study conducted on studying the effect of the Varicella vaccination on the incidence and occurrence of Herpes zoster was studied with the help of mathematical modeling for three European countries- namely Finland, UK and Italy (Poletti et al., 2013).
Authorship- The authors of the particular article includes mathematicians, statisticians, public health analysts and economists and epidemiologists from various countries in Europe including Italy, UK and Finland. There seems to be no conflict of interests of the authors or competing interests with anyone. The qualifications and the affiliations of the authors do not pose any kind of threat for bias in the paper. The respective qualifications help in strengthening the analysis and methodology of the research article.
Research questions- The specific research aims and objective of the research include evaluating the effect of varicella-vaccination on the epidemiology of herpes zoster in three European nations. The research question is focused and extremely specific. The significance of the topic is clearly elaborated and identified by the authors in terms of rising evidence of incidence of Herpes zoster from countries with mass immunization of Varicella. Adequate literature review has been done to identify the significant research gaps and an improved mathematical model has been developed for the same.
Research design- The methodology adopted in the paper is a quantitative analysis by the use of mathematical modeling to predict the occurrence and impact of varicella vaccinations on the occurrence of herpes zoster. The model used has been refined and improved by the authors based on the research gaps assessed in terms of reducing the structural uncertainty around the model as much as possible. The choice of design and methodology adopted is adequate for predicting the effect and establishing the findings for the required aim and objective of the paper as well.
Data collection- The data from the three different countries was adequately collected from the largest ever database on Varicella sero-prevalence in Europe for the three countries. The database is collected from the largest ever population based study conducted by the European sero-epidemiological network. Proper age and country-specific data was collected for all the three countries and the total sample size was around 2000 which is the standard that is considered optimal for the conduction of a study like this. The sampling technique was uniform in which the samples chosen from all the three countries had utilized a uniform method of serum collection.
Data analysis- The data was analyzed using quantitative methodology- by employing a mathematical model for the analysis. The model simulation was parameterized in various steps and the incidence was calculated based on that. Also, there was evaluation of uncertainty as well that was conducted in order to remove the structural uncertainties and produce the best fitting configuration for calculating the incidence of Herpes zoster. The results were combined effectively and it was reasonable to do so to come to a conclusion about the relationship between the varicella vaccination and incidence of herpes zoster.
Discussion- The results of the findings showed that unlike the previous evaluations based on simulation models, this study shows increased incidence of herpes zoster after varicella immunization is not an established fact and that it rather depends on the boosting intensity, based on the presence and absence of certain factors which may or may not depend on the changes in varicella circulation due to mass immunization. It showed that an increase in the incidence of HZ is most probable in countries where the rate of incidence is lower in the absence of immunization due to higher force of boosting- in Finland; and the increase in HZ cases might be minor in countries where the boosting force is milder- like in the UK. The results from the study can be effectively used for application in the general population to help in the reduction of the burden of chicken pox more significantly. Also, all the necessary results have been considered specifically in the study and have been effectively linked to the main topic, for example- the incidence of herpes zoster as well. Adequate discussion based on the findings has been done with a focus on the strengths of the study such as comparing data from different countries. The study suggests an equalizing role of vaccination which is significant when considering from an international, e.g. European, policy making point of view.
A randomized control trial was conducted to study the efficacy of the mono-valent vaccine usage and to compare it with the usage of measles-mumps-rubella vaccine (MMR-V) to protect the children against varicella and chicken pox (Prymula et al., 2014). The research question was clearly identified and specifically focused on.
Authorship- The authors of the particular article includes pediatricians, doctors, public health analysts, epidemiologists, pharmacists and immunologists from various countries including Italy, Poland, Romania, Russia and USA. There seems to be no conflict of interests of the authors or competing interests with anyone. The qualifications of the authors do not pose any kind of threat for bias in the paper. The respective qualifications help in strengthening the analysis and methodology of the research article. However, the affiliations of certain authors to the GSK vaccines might pose some conflict of interest and bias based on their professional affiliations to the particular vaccine producing organization. The research was also solely funded by GSK and was analysed based on a pre-specified analysis plan by the GSK.
Research questions- The specific research aims and objective of the research include assessment and comparison of the efficacy of protection achieved against varicella in children by adopting two different methodologies of treatment- one dose of varicella and two doses of MMRV. The research question is focused and extremely specific. The significance of the topic is clearly elaborated and identified by the authors in terms of increasing adoption of varicella as a part of routine immunization technique and deciding on a particular protocol for the same. Adequate literature review has been done to identify the significant research gaps and an improved research design has been designed to conduct the randomized control trial.
Research design- The methodology adopted in the paper is the use of an observer-blind, randomized control trial conducted in ten European countries where the participants have been divided randomly in a ratio of 3:3:1. The participants have been divided into three groups based on the different treatment groups- one with MMR vaccine, group MMR along with varicella, and the third group with; third with group MMR alone. The choice of design and methodology adopted is adequate for predicting the effect and establishing the findings for the required aim and objective of the paper as well.
Data collection- The participants from the 10 different countries were adequately selected based on purposive sampling. A total of 200 participants were selected from each country. A total of 111 study centres were established in the 10 countries with a total of more than 5000 children. The eligibility criteria was specified clearly- healthy children from age 12 months to 22 months based on the aim of the research. Proper age and country-specific sampling was done. An adequate, sequential, scientific procedure was followed to confirm the cases of varicella. The sampling technique was uniform in which the samples chosen from all the ten countries, in each group, had utilized a uniform method of vaccination schedule.
Data analysis- The data was analyzed using quantitative methodology- by employing statistical analysis technique involving PAAS software. The results were combined effectively and it was reasonable to do so to come to a conclusion about deciding on which kind of dosage of the vaccination should be used.
Discussion- The results of the study showed that the efficacy of the MMRV- when administered in two doses was close to 95% against all varicella and it was around 99% against moderate to severe varicella. The two dose protection of MMRV was greater than the one dose varicella vaccine, which only showed 65% efficacy against all kinds of varicella and 91% efficacy against moderate to severe type of varicella. Although, these results describe only the first 3 years of follow-up, more data in terms of long term protection is expected with the analysis of 10 years follow-up in the same study cohort. The results of the study can be applied to the general population to reduce the burden of chicken pox effectively. Moreover, all the important outcomes have been considered in the study effectively. Adequate discussion based on the findings has been done with a focus on the strengths of the study such as comparing data from different countries.
A study conducted on assessing the impact of the Varicella immunization on Herpes zoster was studied by using mathematical modeling for three European countries- namely Finland, UK and Italy which showed that the occurrence of increased incidence of herpes zoster after varicella immunization is not an established fact and that it rather depends on the boosting intensity, based on the presence and absence of certain factors which may or may not depend on the changes in varicella circulation due to mass immunization. It showed that an increase in the incidence of HZ is most probable in countries where the rate of incidence is lower in the absence of immunization due to higher force of boosting- in Finland; and the increase in HZ cases might be minor in countries where the boosting force is milder- like in the UK. It also established the greater fact that there exists an equalizing role of vaccination significant and important which should be considered when deciding upon policy for vaccination (Poletti et al., 2013). It clearly concluded that the use of varicella vaccination alone is not responsible for the occurrence of HZ and its usage is contributing significantly in reducing the morbidity, mortality and incidence of chicken pox as well.
The study conducted by Prymula et al., (2014) also stated that the use of varicella vaccine was most effective in reducing the mortality and morbidity of chicken pox. And, it thus compared and established that thee monovalent vaccine for varicella was an effective intervention against the vaticella virus. It showed an average 95% efficacy against the chicken pox virus, out of which 94.9% was against all types of varicella and around 90% against moderate and severe kind. Common adverse effects reported were redness at the site of injection and high temperature in the likes of a fever- upto 37 degrees. It was effectively concluded that the vaccine can be used against the varicella virus in children to prevent infection and chicken pox with high-safety profiles.
It can be safely concluded that chicken pox is a serious health concern and a public health issue and it could prove to be life-threatening and fatal for children as well. It can be prevented by the proper immunization of children with the use of varicella vaccine and it has been introduced in the routine immunization schedule as well in most countries. However, it has still not been adopted by the Government of the United Kingdom on the basis of the increased susceptibility and reduced immunity of the adults against the virus and increased incidence of shingles in the adults. This shift of the disease in the higher age group has often been considered as the reason for not adopting the routine plan. However, evidence shows that the varicella vaccine is effective against chicken pox and it does not directly cause an increase in the incidence of shingles in the older population. Rather, the increasing incidence of shingles in the older population is more dependent on the boosting factors of the communities. It has been observed from the discussion and appraisal around the articles that the varicella vaccine is effective against the varicella virus and has high-safety profiles against it as well. Also, its cost-effectiveness can be improved if it was combined with some other vaccination to prevent the development and occurrence of shingles in the adult population in the United Kingdom. The uncertainties revolving around the shift in the age group for the incidence of varicella versus zoster need to be balanced against the over-all benefits of the immunization of the children to prevent the occurrence of disease and its supposed, potential complications as well. The evidence clearly points out to the fact that there is waning of evidence against decreasing immunity in individuals with vaccination and associated occurrence of Herpes zoster with the use of vaccination. Similarly, the epidemiological concernsabout the uncertain effect on Herpes zoster is no longer being linked to the Varicella immunization.
Hence, this strong base of evidence and examples from other nations must be considered by the public health specialists, epidemiologists, policy makers and immunologists and focus on inclusion of the varicella vaccine as a part of the immunization regimen for the children. Also, further research should be warranted in terms of measuring its cost-effectiveness and over-all effect on societal savings as well. Also, equal attention should be given to the potential harms if any develop for the older, adult population.
Amirthalingam, G., & Ramsay, M. (2016). Should the UK introduce a universal childhood varicella vaccination programme? BMJ, 101(1), 1-10.
Ayoade, F., & Kumar, S. (2017). Varicella zoster (Chickenpox). StatPearls, 1(11).
Damm, O., Ultsch, B., Horn, J., Mikolajczyk, R. T., Greiner, W., & Wichmann, O. (2015). Systematic review of models assessing the economic value of routine varicella and herpes zoster vaccination in high-income countries. BMC Public Health, 15(1), 533.
Gray, S. J. (2017). G142 (P) Should varicella vaccination be added to the UK immunisation schedule for healthy children? Archives of Disease in Childhood, 102(5), 58-59.
Hobbelen, P. H., Stowe, J., Amirthalingam, G., Miller, L., & van Hoek, A. J. (2016). The burden of hospitalisation for varicella and herpes zoster in England from 2004 to 2013. Journal of Infection, 73(3), 241-253.
World Health Organization. (2016). Background paper on varicella vaccine SAGE Working Group on Varicella and Herpes Zoster Vaccines. DOI: http://www. who. int/immunization/sage/meetings/2014/april/1_SAGE_varicella_background_pap er_FINAL. pdf.
Wutzler, P., Bonanni, P., Burgess, M., Gershon, A., Sáfadi, M. A., & Casabona, G. (2017). Varicella vaccination-the global experience. Expert Review of Vaccines, 16(8), 833-843.
Poletti, P., Melegaro, A., Ajelli, M., del Fava, E., Guzzetta, G., Faustini, L., & Manfredi, P. (2013). Perspectives on the impact of varicella immunization on herpes zoster. A model-based evaluation from three European countries. PloS One, 8(4), e60732.
Prymula, R., Bergsaker, M. R., Esposito, S., Gothefors, L., Man, S., Snegova, N., & Vassilev, V. (2014). Protection against varicella with two doses of combined measles-mumps-rubella-varicella vaccine versus one dose of monovalent varicella vaccine: a multicentre, observer-blind, randomised, controlled trial. The Lancet, 383(9925), 1313-1324.
Remember, at the center of any academic work, lies clarity and evidence. Should you need further assistance, do look up to our Nursing Assignment Help
Proofreading and Editing$9.00Per Page
Consultation with Expert$35.00Per Hour
Live Session 1-on-1$40.00Per 30 min.
Doing your Assignment with our resources is simple, take Expert assistance to ensure HD Grades. Here you Go....