Case Study For Global Health And Sustainability - Hepatitis E

Hepatitis

Discuss about the Case Study for Global Health and Sustainability hepatitis E.

Hepatitis E virus infection is a significant public health concern internationally, and the incidence of people with Hepatitis E is growing day by day. It is a major cause of enterically transmitted hepatitis, and it is turning out to be an endemic in developing countries where it has caused increased morbidity. Millions of people are living with viral hepatitis, and many are at risk of developing the severe chronic liver disease and transmit the infection unknowingly to other people. It is not just confined to travelers returning from the endemic region but also in older men. The major problem identified for its endemic is that it has a poor prognosis due to the existence of other chronic liver disease and being often confused with drug-induced liver injury. Proper treatment also becomes a problem due to uncertainty about the source and route of infection. Due to the endemic, it will be a huge burden on the health care system and will affect people both financially and physically. There is a particular population which is at more risk of the disease than others. Viral hepatitis has not received the desired attention from global health community. Since the problem has not been addressed in a serious way, it will have its effect on human health worldwide. The proposed solution is to improve the global health treatment model by increasing the testing of hepatitis in the high-risk area, arranging for affordable treatment options, creating awareness about the disease and looking into discoveries of Hepatitis E virus to understand the cause of disease. The global health community should work towards increasing sustainability and resilience of the disease and make it manageable for people. The report will also look into incidences of infection worldwide and develop an evaluation strategy for proposed solution.

Hepatitis is a viral infection leading to inflammation of the liver. Different type of hepatitis virus types A, B, C, D and E are responsible for the cause of hepatitis worldwide. It may also occur due to auto-immune disease and toxic substance like alcohol and drugs. All the types of diabetes is a great concern for global health because of the burden of illness and the mortality associated with its epidemic outbreak (Cooke et al. 2013). The epidemiology of the disease, diagnosis, prevention, and treatment process varies for all types of hepatitis. Hepatitis type B and C is the most common cause of liver cirrhosis and cancer. Hepatitis B, C, and D occurs due to parenteral contacts such as infectious blood and other body fluids. Hepatitis A and E are transmitted by fecal-oral route either by the person to person contact or by ingestion of contaminated food or water. All types of hepatitis virus are transmitted through contaminated blood products, a medical procedure using the contaminated equipment. Hepatitis B is transmitted from mother to baby during birth and by sexual contact. Acute infection leads to symptoms like jaundice, nausea, vomiting and abdominal pain (Rehermann 2013).

History of the Problem

Since the focus is on Hepatitis E, more detail will be provided regarding it in this section. Hepatitis E virus (HEV) is mostly transmitted through faecal-oral route due to contaminated water or foods. It is a primary cause of hepatitis endemic worldwide and is becoming a significant concern for the global health. Vaccines for HEV infection developed in 2012, but it is not widely available. Humans are a natural host for the virus and areas with poor sanitation are at more risk of hepatitis virus transmission. Consumption of uncooked shellfish has also been identified as the source of disease in the endemic area (Hoofnagle et al. 2012). The incubation period for the virus ranges from 3 to 8 weeks but the period of its communicability is not yet discovered. The virus causes acute sporadic and epidemic viral hepatitis. The symptoms develop after 15-60 days of exposure (Kamar et al. 2014). Symptomatic infection is seen in young adults but in children the disease is mostly asymptomatic which cannot be easily diagnosed. The typical signs and symptoms of hepatitis E are yellowing of skin and eyes (jaundice), dark urine, pale stools, anorexia, enlarged liver (hepatomegaly), abdominal pain, nausea, vomiting, and fever (Crespo et al. 2012). The symptoms are not distinguishable from the symptoms experience in the acute phase of illness. The infection last for 1 to 2 weeks. The disease may lead to fulminant hepatitis which is an acute liver failure in very rare case. Pregnant women are at risk of obstetrical complications, and the rate of mortality is about 20% in the pregnant women. Chronic hepatitis E infection and reactivation of infection is seen in immunosuppressed individuals (Labrique et al. 2012)

Although most people recover from the illness completely, the mortality rate is high mainly in pregnant women reaching their third trimester. It can also have grave consequences in patients with preexisting chronic liver disease which results in decompensated liver and death. The mortality rate is high in solid organ transplant patients on immunosuppressive therapy. HEV genotype 1 and two does not cause chronic illness, but a significant number of cases of hepatitis is E progressing to chronic liver disease has been reported (Krain et al. 2014).

HEV belongs to the genus Hepevirus in the Hepeviridae family. It is a single-stranded positive strand RNA virus. There are four genotypes of HEV. HEV was not recognized as a health concern until the 1980s. Till then all the endemic was related to hepatitis A virus. The development of serological assays proved HEV to be endemic in tropical and sub-tropical countries with major outbreaks reported in India, Southeast Asia, Africa, and Mexico. Most epidemics have been caused by contaminated water following heavy rainfall. HEV infection has been affecting humans for centuries, but it has been recognized as a public threat only in the end of 20^th century (Messina et al. 2015). The HEV infection was first clinically described after its outbreak in Delhi in 1955. Later it was characterized on clinically, morphologically, serologically and on molecular levels. After the development of serological and molecular diagnostic tools, it has received global attention. It became the focus of Viral Hepatitis Prevention Board meeting in Belgium and International Vaccine Institute in Korea. The true global burden of the disease has not been assessed, and international organizations are researching on it. Sequencing of HEV-RNA revealed that genotype 1 and 2 mostly infects humans and genotype 3 and 4 primarily infect humans as well as animals like pigs, boar, deer, etc (Abdelrahman et al. 2015). About 80% patients with HEV infection were reported to have traveled to HEV-endemic countries. So it is self-limiting disease causing significant morbidity and having risk only in pregnant and immunosuppressed person. International travelers are at risk of infection. New vaccines have been introducing, but full assessment regarding prioritization of intervention and allocation of resource is still in progress. It is also crucial to make people aware of not eating raw meat and uncooked sausages (Scobie and Dalton 2013).

Global Burden of the Disease

Viral hepatitis is a global health concern. It has caused 2.7 % death worldwide caused due to viral hepatitis and liver disease. HEV infection has occurred both sporadically and in the epidemic. True prevalence is not known it has just been estimated that about one-third of the world population has been infected. Genotype 1 HEV is an endemic in developing region like Asia, Africa, and South America. Genotype 2 HEV is common in the population of Mexico, Chad, and Nigeria. Autochthonous hepatitis E cases of genotype 2 are found in developing regions having high pig population. 17-20 Genotype 4 cases are found in countries like Japan, China, Taiwan and in India (Messina et al. 2015).

Hepatitis E is common in regions having problems of water supply and inadequate environmental sanitation. Some of the outbreaks have occurred in areas of conflict such as war zones and refugee camp. The disease is mostly prevalent in Asia, Middle East, Africa and Central America. People living in a temporary settlement after any natural disaster and travelers visiting endemic regions are more at risk of the disease (Bruggmann et al. 2014). According to World Health Organization estimate, 20 million hepatitis E infections, 3 million symptomatic cases, and 56600 deaths has been reported worldwide. Global burden of disease is calculated by a systematic review of disease in the target area. One global burden of disease study showed that HEV genotype 1 and 2 has caused 20 million HEV infection, 3000 stillbirths, and 3.4 million symptomatic cases (Gower et al. 2014).

Hepatitis E is common worldwide, but its prevalence is highest in East and South-East Asia. The endemicity report of Hepatitis E in South-East Asia region states that less than 50 % population is exposed to the infection in the eastern region and greater than 90% in the southern region. Eleven member states of WHO comprise South-East Asia region. It has one-fourth of the population living in the area and carries 30% world's total burden of disease (Franco et al. 2012). Every year about 14 million cases of Hepatitis E infection have been reported in the region. It contributes to half of the global burden of disease. In East Asia, the major outbreak has been reported in China (Rein et al. 2012). The seroprevalence of anti-HEV antibody in this region varies from 10 to 50% indicating it as hyper-endemic in the region. The incidence of HEV is more than 25 % of people below 50 years. Hepatitis E outbreak was also reported in the Central African Republic, and the seroprevalence rate is 24% in the Central African Republic. In Central America also Hepatitis E was reported in Mexico in 1980 (Lim et al. 2013).

After analyzing the report on Hepatitis E disease and its global burden worldwide, it is necessary to identify issues related to sustainability in the problem. What has lead to the disease becoming a global public health concern needs to be determined. There may be flaws in specific country's health model system. This section will describe the issue that has caused morbidity and mortality worldwide.

Inadequate serological assays and global burden data: The Major problem is that there is limited surveillance for Hepatitis E disease and lack of awareness of disease occurrence. No apparent disease distribution is available; all are a just estimation. Seroprevalence of antibodies to HEV is a marker for previous exposure to the HEV (Junge et al. 2013). But getting seroprevalence data is challenging because of lack of comparability of results of different assays and presence of various genotypes with different disease patterns. Sometimes the serological test cannot clearly distinguish between genotypes and no reliable mathematical modeling data to determine the degree of disease burden. The laboratory assay results are generally poor meaning the poor level of diagnosis and many not getting diagnosed on time (Abravanel et al. 2014).

Data for policy and action: The exact mechanism of high mortality rate in pregnant women is not known. Persons with the pre-existing chronic liver disease develop severe morbidity post HEV infection. The data for this in developed countries is limited, and there were incidences where the drug-induced liver injury was erroneously diagnosed instead of the real culprit Hepatitis E. So, repeated misdiagnosis is a cause of concern. Countries lack adequate surveillance system, and so evidence-based policy decisions cannot be taken (Everson et al. 2013).

Challenges in transmission: Very few WHO member states have policies to provide HEV vaccine at birth and till now only 27% has received the vaccine. Though the vaccine has been introduced worldwide in 179 countries in 2010, still the global coverage of vaccine has not reached the estimated target of 90 %. The vaccine coverage till now is only 75%. Standard precaution for preventing the risk of transmission has not been implemented by healthcare facilities. This has lead to increased risk of transmission due to the negligence of health care. Sometimes this has lead to misdiagnosis of HEV (Spradling et al. 2013).

Problems of poor sanitation: Contaminated food and water is the primary source of HEV transmission. Common routes of transmission include- fecal-oral transmission due to contaminated drinking water, food-borne transmission by food products derived from infected animals, zoonotic transmission from animal to humans, transmission through infected blood products and mother-fetus transfer.  But currently around 37% of the world population does not have access to proper sanitation facilities and 11% do not have the resource to clean drinking water. So many people are living in unhygienic condition exposed to diseases. In many countries donated blood are not screened for transmissible infection (Singh et al. 2013).

Lack of access to proper care and treatment:  The health care system is also at fault and has contributed to the endemic. Health care lacks professional competency for diagnosis and treatment. The poor quality diagnostic is mostly seen because of resource limitation and below standard regulatory policies.

So health organizer has the responsibility to mobilize support and develop a specific strategy to increase surveillance and prevention of HEV. The report on disease burden estimate and global prevalence needs to be improved by arranging for study in endemic and high prevalence areas. This is necessary to know the exact impact of the disease in the vulnerable and risky population. There were defects in serological assay report and mathematical modeling data leading to erroneous diagnosis. This is a great cause of concern. So public health department in different countries needs to support the development of scientific research on the problem. HEV infection is known to occur in the region with an acute shortage of water supply, poor hygiene, and sanitation, so adequate steps need to be taken for cleanliness drive in the country (Nelson and Williams2013).

There should be a national level strategy for the prevention and control of viral hepatitis. The critical framework for developing resilience and controlling hepatitis virus infection should be as follows:

The central vision should be to stop viral hepatitis transmission, and the change should be resilience and sustainable.

Arranging for proper access to safe and efficient health care environment so that morbidity and mortality associated with the disease could be reduced.

For the welfare of the community, there should be efforts to reduce treatment cost and increased surveillance of HEV infection in people. This will reduce socio-economic impact of viral hepatitis both at the individual level and population levels (Franco et al. 2012).

After analyzing the key challenges and problems in HEV infection worldwide, the following intervention is needed:

Increasing awareness and mobilizing resources: The health professionals and policy makers will play a significant role in raising awareness among the public in endemic regions. WHO and member countries can provide support by mobilizing resource and supporting countries with limited resources (Wedemeyer et al. 2014).

Creating an evidence-based policy for reducing the global burden of disease: No proper data on global prevalence of HEV is available. So action should be taken to increase collection of epidemiology data from different countries and analyzing global estimates for viral hepatitis. The government of endemic countries should arrange for conducting countrywide response workshop on the burden of the disease in selected country (Papatheodoridis et al. 2016).

Developing methods for preventing virus transmission: Public health agency should promote the expansion of immunization drive across country. Although the vaccine is available vaccine coverage is not adequate. So, medical staff can contribute in protecting high-risk groups against the disease. They should be efforts to implement innovative immunization program and other approaches shortly. Behavioral and structural intervention include encouraging safe blood transfusion and creating facilities for safe food and water in countries and arrangements for proper disposal of sanitary waste (Bennett et al. 2014).

Strategies for care and treatment: It is the responsibility of health care department to review treatment guidelines and remodel it according to inefficiency in the previous approach. Every diagnostics and therapeutics should be prequalified, and updated tools should be there for serological assessments. To tackle problems of high-cost treatment, they should develop modern scientific tools and negotiate with suppliers to reduce drug price. In places where the disease is endemic, WHO can play a role in assisting countries in developing national strategies (Curry et al. 2015).

A comprehensive approach for prevention of viral hepatitis includes different levels of prevention.

Primary prevention: Steps of primary prevention includes:

• Increasing availability of HEV vaccines and getting it licensed in countries where it is not available.
• Increasing awareness of HEV infection in the community.
• Promoting blood safety strategies by assuring quality-assurance screening of all donated blood samples.
• Taking infection control precaution in health care and giving training to health care staff related to occupational security measures.
• Making arrangements for safe food and water which provides protection against HEV infection (Evans 2013).

Secondary prevention:

• Many people living with HEV infection are not diagnosed, and they are often confused with drug-induced liver injury. So early diagnosis is the key to receiving adequate medical support and preventing disease transmission. The advantage of early diagnosis is that it allows people to take precaution against damaging the liver. The precautionary steps for preventing damage to liver includes avoiding alcohol, drugs and tobacco which are harmful to the liver (Nelson and Williams 2013).
• The introduction of a proper screening test that confirms the diagnosis is essential. Blood donors should be appropriately counseled if reactive results are detected in them. This will provide them opportunities for early diagnosis. Medical support should also be given to an asymptomatic individual who comes to donate blood (Hewitt et al. 2014).
• Anti-viral drugs against HEV are not readily available. Advances and adequate research in therapeutics will lead to the development of new oral anti-viral medicines. The major focus should be on ensuring access to treatment regimens in lesser developed areas having a resource problem (Lawitz et al. 2014).

Since Southeast Asia is a major region for HEV infection, it has been selected for delivering the intervention. Involvement of WHO member states in Southeast Asia is essential in this regard. They should be encouraged to do a survey that will help them define proportions of hepatitis infection and death cases registered in the country. Implementation of national policy on the screening of pregnant women will be beneficial (Centers for Disease Control and Prevention 2012). The health professionals in Southeast Asia will be adequately trained to develop competencies in treating patients with HEV infection. The essential drugs for treating disease will be effectively delivered in the country. Common drugs that will be readily available will include drugs like lamivudine, interferon alpha, and tenofovir (Hosaka et al. 2013). WHO will assist member countries in developing a national plan for E hepatitis prevention, estimating national burden and increasing viral hepatitis surveillance. No treatment will reduce the course of hepatitis E infection. But is the best approach and primary focus will be on giving treatment to symptomatic pregnant women and asymptomatic individuals in Southeast Asia. They will be provided Ribavirin treatment for 21 days to improve the function of liver enzymes (Charlton et al. 2015). The risk is also high in patient undergoing organ transplant. For treating such patients, immunosuppressive therapy will be reduced to increase viral clearance. If immunosuppressive therapy is not reduced in any patient, then anti-viral therapy will be provided to them. For patients with chronic HEV, ribavirin monotherapy for three months will clear HEV. Pegylated interferon alpha therapy for one year will also lead to sustained HEV RNA in patients who have undergone liver transplantation (Lawitz et al. 2014).

In South-east Asia, there is a high level of water contamination due to polluted water and garbage disposal in river water. So the plan is to maintain quality standards of public water supplies and introducing proper disposal system to remove sanitary waste. In National awareness programs in member countries of South-east Asia, the individual member will be made aware of hygienic practices such washing hand with clean water and avoiding water whose purity is not known. To prevent contamination through food, they will be taught to avoid uncooked food (Cosgrove and Rijsberman 2014).

Sustainable control steps will be taken by the health department to remove unhygienic water from poor sanitation area. Water hygiene and sanitation in any area is affected by factors like increasing population density, growing demand for water but limited water supply, climate variability and activities like construction of dams, roads, deforestation, agriculture, etc (Gorenflo and Warner 2016). The population density of Southeast Asia is also high, and this has made the region more vulnerable to waterborne diseases. This might also be the cause for the high prevalence of Hepatitis E infection. There is great climatic variability in Southeast Asia. Floods and drought affect water availability and water quality. If there is limited access to water, people is forced to drink contaminated water leading to the endemic. So the plan is to implement sustainable water use which will eliminate the problem. It will teach people to endure situations shortly without compromising on hydrological cycle of eco-system (Bain et al. 2014).

For successful implementation of above approach and to reduce the burden disease, the plan is to research on sustainable water management. The plan is to implement water treatment system which serves the purpose of preventing HEV illness. Sustainability plans will be dealt with using interdisciplinary tools that will look into aspects of social, physical and ecology of targeted environment (Dora et al. 2015). An ecological perspective of research will help in understanding how to control transmission. The focus will be on the environmental determinant of HEV infection by increasing anthropogenic changes to the physical environment. The virus is transmitted to the environment by human feces and contact with infected animals (Ford et al. 2014). So, personal level of awareness is also necessary. Many people move about in poor sanitation area, and they are not aware of ways of transmission due to lack of education, underdevelopment, and poor education. So it is necessary to educate the mass about how the disease is transmitted by this means and giving them knowledge about the interaction between the virus and environmental factors. Once people are aware of the causes of disease, they will themselves take adequate strategy to tackle the problem (Marlow et al.  2013)

Conclusion

From the whole study, it can be concluded that HEV infection is a global health concern worldwide and appropriate strategy for prevention of the disease is essential to look into the growing incidence of illness and determine preventive strategies in selected population. This briefing report was focused on Hepatitis E infection worldwide, and this briefing document gave detail on HEV infection worldwide. The briefing report was prepared to keep the theoretical framework of sustainability and resilience in mind. The briefing report gave detail on the cause of viral hepatitis and different types of hepatitis virus. It explained the cause of HEV and its associated symptoms. It emphasized on the individuals who at more risk of developing the disease. It gave detailed information about estimated burden of HEV worldwide and its estimated prevalence in the world. It was found that there is no available data for calculating global burden of disease. Since the population chosen for the study is South-East Asia, reports were provided on the mortality and morbidity rate of HEV in South-East Asia. After the detailed analysis of HEV infection worldwide, potential drawbacks and problems in HEV treatment were identified. Based on the challenges and problems faced by health care professionals and patients, intervention strategy for the disease was described. Different level of the surveillance program by the government was described, and it gave detail into how the intervention will be delivered in targeted population. It gave sustainable programs for improving water quality and sanitation in affected area. Changing anthropogenic activity will also be crucial for preventing hepatitis E virus transmission and its infection. It is estimated that if serious steps are taken, endemic countries can effectively manage the disease.

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