Global Health Challenges for Vaccines

Vaccines – a miracle and a dilemma: vaccine issues in Global Health

Introduction

With my General Practice tutor away on vocation there was a need to plug a gap in my timetable. I was assigned to the practice nurse who ran the travel vaccination clinic and the general vaccination clinic for babies, children and adults alike. Whilst working in general practice I saw at first hand the role of vaccines in preventing communicable disease. I observed the education being provided to patients and on my second day I assisted in giving the standard UK vaccinations for older adults, vulnerable adults groups and then infants and young children.  As part of my experience I was observed by the practice nurse educating patients on the benefits of vaccination. The fact that these are free in the UK made me come to view vaccinations as something akin to a gift or a medical miracle  in that they could prevent disease and preserve health. These were gifts that I was being allowed to administer daily for a few days and it made me reflect on the extent to which other countries enjoyed the same gifts. For these gifts/vaccines to be accepted I also have had the opportunity to reflect upon the importance of prior education and the part these gifts/vaccines play in preventing national and global epidemics. I then considered whether it was possible to prevent a communicable disease epidemic and these thoughts underscore this essay where I explore the issues surrounding vaccines from a global health perspective. Finally, I end with some more reflections on vaccines and global health in regard to my not too distant role as a doctor.

When we talk about an epidemic, an epidemic is defined as “the appearance of a particular disease in a large number of people at the same time”.^[1] This allows for the possibility of both communicable and non-communicable disease epidemics; communicable diseases are infectious diseases, while non-communicable diseases are non-infectious diseases such as diabetes”.^[2] Moreover, epidemics can last from just a few weeks to many years.^[1]

A dynamic planet

For an epidemic to occur, there is a complex interaction of population factors, environmental factors and pathogen characteristics and I will address each of these in turn. Population factors determine a person’s susceptibility to infection and these include a person’s nutritional status interacting with a person’s immunology and genotype and by their nature these are factors which are not fixed.^[3]

Similarly, environmental factors include a complex of quality of health care and its accessibility, housing quality and particularly overcrowding and sanitation and climate all of which are dynamic and  can  interact to affect an individual’s exposure to disease as well as  the  type of  disease.^[3]

Finally, for an epidemic to occur, there are pathogen characteristics. Pathogen characteristics stem from their uniqueness which to survive requires them to mutate or evolve by overtaking the body of their host i.e. the person that it seeks to infect. It is this complex interaction of these pathogen characteristics with the dynamic characteristics of its potential hosts in their dynamic environments which offers a platform for epidemics to take hold.^[3] In recent decades the increasing transnational interdependence or globalisation has compounded this.

Whereas the complex interaction of population, environment and pathogen characteristics suggest real risk and perhaps give rise to a sense of inevitability of future epidemics and pandemics, this is not to say that these risks cannot be reduced. It has even been possible to eradicate some infectious diseases as was the case with Smallpox in 1980. In the case of Smallpox the discovery of a vaccine lay at the heart of this success and prompted something of a vaccine revolution in an attempt to protect public health from infectious disease.^[4] This has been made possible by our greater understanding of the causative agents and biology of disease. Vaccination offers the opportunity to tackle infectious disease, but vaccines are not without their issues. For instance: there can be serious unexpected outbreaks of known and unknown or emerging infectious diseases. These may or may not be prevented but need to be contained. These diseases are more likely in environments that confer risk such as during war time and when populations are on the move as with refugees. These diseases are also more likely in the presence of natural disasters such as with floods, where there is inadequate clean water and inadequate sanitation and hygiene. Prevention of infectious disease in such situations is made all the more difficult because vaccine uptake depends on adequate infrastructure and above all forward planning.^[5]

Moreover, vaccinations require research and development which is expensive and there is a delay in the time vaccines take to be developed and the time they become available for use. A successful vaccination programme requires surveillance and monitoring; there needs to be available records and reliable record keeping. Vaccinations need to be available when required and there is a need for suitable storage when not in use and when in transportation. For a vaccination programme to be truly successful there needs to be herd immunity, which is where a significantly high percentage of individuals need to be vaccinated in order to prevent spread. Then for the vaccine to be acceptable it needs to be efficacious, have few side effects or contraindications and patients need to be educated to ensure take-up. These are more complex issues than the simple education, administration and documentation that I both observed and took part in whilst working in general practice.^[6]

I shall explore the above issues with case studies both here and abroad.

The Known Infectious Disease (KID) and the new Emerging Infectious Disease (EID)

There are differences between using vaccines to manage Known Infectious Disease (KID) and trying to develop a vaccine for a new Emerging Infectious Disease (EID). Even when we have a KID the ability to vaccinate and the success of vaccination is dependent on a number of factors as discussed in the case studies below.^[6]

Known Infectious Disease (KID)

Whereas it has been possible to eradicate some diseases such as smallpox, eradication of other diseases remains a challenge. For instance, although cases of measles are now thankfully rare, eradication has not been achieved because of its requirement of herd immunity.^[7] The vulnerability of vaccines such as the MMR with its 1990’s negative press at the hands of ill-informed journalists working according to their own agenda underlies the vulnerability of vaccines to safety fears and dispute about their efficacy.^[8] Although the fear over the MMR vaccine has largely subsided in relation to younger parents, I still found persisting concern in a few of the older new parents for whom the earlier scare was still within their memory. This demonstrates both the fragility of vaccines and some of the issues when it comes to eradicating infectious disease.^[8] It also underscores the need for good quality education and research in the prevention of disease.

The International Co-ordinating Group (ICG) was established in 1997 to ensure vaccines are available for future epidemics. Vaccines are stockpiled to treat cholera, yellow fever and meningitis and these diseases are constantly monitored to ensure preparedness so that vaccines should be made available within 10 days of their request.^[9]

When in 2014 South Sudan experienced a cholera epidemic during their civil war, they were prepared for it, having already put in a request from the ICG for 250,000 oral cholera vaccines.^[10] This early request meant that the ICG and South Sudan was able to contain the outbreak in the displaced people living in unsanitary camps. In the vaccinated camps there were only a few isolated cholera cases. However, not every camp got the vaccination. Therefore accurate forecasting and early planning is key.^[10] The situation in South Sudan contrasts with the relative failings to contain the cholera outbreak during the civil war in Yemen in 2017. Yemen’s request for 1,000,000 vaccines came some months after the first reported case which underscores the importance and difficulties associated with forward planning.^[11] Yemen’s cholera outbreak also demonstrates the difficulties in fighting known infectious diseases, for which a vaccine is available, when there is a need to execute a program of vaccination during wartime. Without an improvement in logistics / early intervention, an outbreak can turn into an overwhelming epidemic and a logistical nightmare and this is all the more likely to happen in a conflict zone.^[11,12]

New Emerging Infectious Disease (EID)

The biggest challenge of all is new emerging infectious diseases (EID). The uniqueness of these diseases makes identification / diagnosis challenging and their management is compounded by the unavailability of vaccines. The latter is due in part to the time taken to produce a vaccine coupled with inadequate investment or a failure to invest in research and development whose costs can be prohibitive without financial incentive.^[13]

This need to fight disease using research and international collaborative efforts has been addressed by the Africa Centre for Disease Control (Africa CDC), which was set up last year to co-ordinate and collaborate with regional centres in Kenya, Zambia, Gabon, Nigeria and Egypt. These centres are able to detect their own emerging diseases and thereby help the CDC to conduct forecasting and surveillance of disease in Africa. This should remedy some of the logistical challenges resulting in earlier ICG requests, and should facilitate more suitable treatment and quarantine centres.^[14]

In developed countries and via The World Health Organisation (WHO) there are also attempts made to predict future epidemics.^[15] In fact complex mathematical models are used to forecast epidemics and predict and understand the processes involved in this. These attempts to forecast future disease should render public health interventions such as vaccination more timely and efficacious as well as improve our understanding of the infectious process and quarantine. However, as we have seen in more recent global health epidemics we are still taken off guard with emerging infectious disease as occurred with the 2014 Ebola epidemic in West Africa. The lack of global preparedness and slow response to the emerging disease resulted in more than 28,000 cases and more than 11,000 deaths.^[2]

The WHO belatedly responded with the Ebola Research and Develop initiative, whose aim was to collaborate so as to produce diagnostic kits and a vaccine in a narrow time-frame,^[16] as well as predicting emerging diseases which lack adequate countermeasures.^[15] By prioritizing diseases effective countermeasures can be developed before and in case they are actually needed. However, the lack of clinical cases with which to perform clinical trials makes developing therapies between epidemics quite difficult. However despite this, the Coalition for Epidemic Preparedness (CEPI) provides large financial incentives to enable the development of vaccines that might never be needed.^[17]

Working together: Volunteers, Community Leaders and Government Organisations

Northern Malai and Medecins Sans Frontieres (MSF)

It is not just governments that seek to combat infectious disease. Voluntary organisations such as Medecins Sans Frontieres (MSF) have long been involved in global health. Recently, MSF working with the Mali Ministry of Health and community leaders were successful in vaccinating 10,000 children against eleven diseases in over 37,000 miles of desert in northern Mali.^[18] This successful project demonstrated many of the issues surrounding vaccination. For instance, northern Mali is a semi-desert region with unpaved roads and a nomadic population, this posed particular difficulties in administering three separate doses of vaccines over a number of weeks. The MSF also needed to overcome the problem of storing medicines at between two and eight degrees in a desert environment and successful vaccination was also made all the more difficult as northern Mali is a conflict zone with mined roads.^[18]

Conclusion

The belief that humans have a right to health underscores the need to reduce or eradicate infectious disease. Whereas future epidemics and pandemics are inevitable, vaccination offers the opportunity to tackle infectious disease. The ability of vaccines to prevent disease and preserve life ensures that financial resources are invested in international organisations, whose role it is to forecast disease and particularly those diseases in need of effective countermeasures. This early planning ensures that efficacious vaccines are available for future epidemics.

I explored the issues surrounding the development and use of vaccines from a global health perspective by exploring some communicable diseases at home and abroad. My exploration revealed the difficulties facing health systems in low- and middle-income countries. It also revealed that infectious diseases are more likely in environments that confer risk such as during war time and during natural disasters. These issues are more complex issues than the simple education, administration and documentation that I both observed and took part in whilst working in general practice.

Whilst there have been significant improvements in vaccine development and delivery, vaccination still poses both challenges and opportunities. Some of these challenges and opportunities have been taken up by voluntary organisations such as Medecins Sans Frontieres (MSF). The MSF working alongside government and community leaders have achieved levels of vaccination previously thought to be impossible. Governments and health care workers will continue to need to adapt to both the challenges and the opportunities.

My experience in General Practice, coupled with my research in global health has made me more aware and informed regarding the issues surrounding vaccination. Although, I am unlikely to be involved in research, development and policy formation, I will as a GP play a role in vaccination and my experiences and research means that I have a greater understanding of the need for good quality education for the public, so that I can take a leadership role in vaccination, rather than one where I just follow.

References

• [1] Cambridge Advanced Learner’s Dictionary. 3rd edition. Cambridge University Press; 2008

• [2] Wylie, A. (2018, June 6). Global Burden of Disease [Stage 3 Webinar 1 2018]. In  KCL Webinar Series. Retrieved from https://keats.kcl.ac.uk/mod/folder/view.php?id                =2136641

• [3] CDC, in An Introduction to Epidemiology and Applied Biostatistics. (US Department of  Health and Public Services, 2012).

• [4] Miller M, Barrett S, Henderson DA. Control and Eradication. Jamison DT, Breman JG,  Measham AR, Alleyne G, Claeson M, Evans DB, Jha P, Mills A, Musgrove P, eds. Disease               Control Priorities in Developing Countries. 2nd edition. Washington (DC): World Bank;               2006. Chapter 62.

• [5] Infectious Diseases [Internet]. Pandemic and Epidemic Diseases. [reviewed 2017].  Available from: http://www. who.int/csr/en/ (accessed 16 December 2018).

• [6] Research by Disease [Internet]. Immunization, Vaccines and Biologicals. [reviewed 2018].               Available from: http://www.who.int/immunization/research/development/en// (accessed 16               December 2018).

         [7]  Bester JC. Measles Vaccination is Best for Children: The Argument for Relying on Herd               Immunity Fails. J Bioeth Inq. 2017 Sep;14(3):375-384. doi: 10.1007/s11673-017-9799-4.               Epub 2017 Dec 18.

         [8] Shelby A, Ernst K. Story and science: how providers and parents can utilize storytelling to               combat anti-vaccine misinformation. Hum Vaccin Immunother. 2013 Aug;9(8):1795-801.               doi: 10.4161/hv.24828. Epub 2013 Jun 28.

• [9]  Stockpiling Vaccines [internet]. National Programmes and Systems. [reviewed 2018].  Available from: http://www.who.int/search?q=stockpiling+vaccine&ie=utf8&site=who              &client=_en_r&proxystylesheet=_en_r&output=xml_no_dtd&oe=utf8&getfields=doctpe
  • (accessed 15 December 2018).

• [10] Azman AS, Rumunu J, Abubakar A, West H, Ciglenecki I, Helderman T, Wamala JF,               Vázquez Ode L, Perea W, Sack DA, Legros D, Martin S, Lessler J, Luquero FJ.

o       Population-Level Effect of Cholera Vaccine on Displaced Populations, South Sudan, 2014.

•  Emerg Infect Dis. 2016 Jun;22(6):1067-70. doi: 10.3201/eid2206.151592.

• [11] Al-Gheethi A, Noman E, Jeremiah David B, Mohamed R, Abdullah AH, Nagapan S, Hashim               Mohd A. A review of potential factors contributing to epidemic cholera in Yemen.
•  J Water Health. 2018 Oct;16(5):667-680. doi: 10.2166/wh.2018.113.

         [12]  Federspiel F, Ali M. The cholera outbreak in Yemen: lessons learned and way forward.

•  BMC Public Health. 2018 Dec 4;18(1):1338. doi: 10.1186/s12889-018-6227-6.

• [13] Buliva E, Elhakim M, Tran Minh NN, Elkholy A, Mala P, Abubakar A, Malik SMMR.

o       Emerging and Reemerging Diseases in the World Health Organization (WHO) Eastern Med              iterranean Region-Progress, Challenges, and WHO Initiatives. Front Public Health. 2017 Oct               19;5:276. doi: 10.3389/fpubh.2017.00276.

• [14] Nkengasong JN, Maiyegun O, Moeti M. Establishing the Africa Centres for Disease               Control and Prevention: responding to Africa’s health threats. Lancet Glob Health 5, e246-              e247 (2017).

• [15] WHO, “Annual review of the Blueprint list of priority diseases,” [Internet] A research and               development Blueprint for action to prevent epidemics [reviewed 2018]. Available from:               https://www.who.int/blueprint/en/ (accessed 22 December 2018)

• [16] Ebola research and development landscape of clinical candidates and trials (Public Report               October, 2015               https://www.who.int/medicines/ebolatreatment/rd_clinical_candidates-trials
  • _report/en/ (accessed 23 December 2018)

         [17] Plotkin SA. Vaccines for epidemic infections and the role of CEPI. Hum Vaccin Immunoth              er. 2017 Dec 2;13(12):2755-2762. doi: 10.1080/21645515.2017.1306615. Epub 2017 Apr 4.

• [18]  “Vaccination in the desert”. Without Borders. Medecins Sans Frontiers. 2018, p. 6.