Guidance for contact tracing of cases of Lassa fever, Ebola or Marburg haemorrhagic fever on an airplane: results of a European expert consultation

Impacts of Ebola disease outbreak in West Africa: Implications for government and public health preparedness and lessons from COVID-19

There has been an increase in the outbreak of communicable diseases in recent times; the most recent ones are Ebola Virus Disease (EVD) and COVID-19. These diseases have had different impacts on society and the ecosystem. However, underlying these impacts are the levels of preparedness of governments and public health institutions to mitigate and control these diseases. Therefore, this paper aims to explore these impacts, government and institutional interventions and their nexus towards the effective management of such crises. A critical review of empirical literature was adopted for the methodological approach and narrative synthesis used for analysis. Results show that EVD had diverse impacts on West Africa; economically through the loss of income from economic activities due to widespread sickness among workers and movement restrictions. EVD also had significant social impacts, such as reduced community cohesion, school and business closures, job losses, food insecurity, and high morbidity and mortality. Though some good efforts have been made by different countries in collaboration with international organisations like the World Health Organization to control disease outbreaks more effectively, the recent COVID-19 pandemic has however exposed major weaknesses in the capacity of most African countries to cope. Poor capacity for testing and treatment, inadequate health facilities, poor incentives for health care workers, poor governance systems, poor border control, and awareness and research capacities impacted negatively on the capacity to control disease outbreaks. There is, therefore, a need to strengthen health systems across Africa through improved resource mobilisation, staff training, and coordination of investment strategies to sustain health system preparedness to manage future emerging or re-emerging outbreaks.

Immunological screening of Lassa Virus among Health workers and Contacts of patients of Lassa fever in Ondo State

BACKGROUND

The increasing trends of morbidity and mortality of Lassa fever is becoming more alarming in Nigeria. Information about immune response to the virus is limited. At exposure, the level of immunity plays a vital role in the vulnerability of individuals infected.

OBJECTIVE

Investigating the immune status of health workers, infected cases and contacts of infected cases of Lassa fever in Ondo State.

STUDY DESIGN

Blood samples were collected from 233 individuals comprising 102 health workers, 22 infected cases and 109 contacts of infected cases from Owo and Ose Local Government Areas and transported in triple level packaging. Plasma samples were analyzed for IgG and IgM markers using ReLASV® Pan-Lassa NP IgG/IgM ELISA Kit (Zalgen Labs, LLC, USA) while RNAs extracted from IgM positive samples were analyzed for LASV RNA according to manufacturers' instructions.

RESULT

Among the health workers, 20/102 (19.6%) and 2/102 (2.0%) were IgG and IgM positive respectively. While 16/22 (72.7%) and 14/22 (63.6%) were IgG and IgM positive respectively among the infected cases. Of the contacts of infected cases screened, 64/109 (58.7%) were IgG positive while 4/109 (3.7%) were positive for IgM. There was no detectable LASV RNA in the samples analyzed.

CONCLUSION

These findings suggest that majority of the health workers are naïve to the virus and hence may be prone to the viral infection. It could also be suggestive that a good personal protective procedure is been practiced by the health workers, hence the low exposure. However, most of the contacts of infected cases show exposure to the virus.

Lassa virus RNA detection from suspected cases in Nigeria, 2011-2017

Introduction

The diagnosis of Lassa fever is crucial to confirm cases, as well as to control/prevent nosocomial and community-based transmission and initiation of treatment, which is still limited in the country. Thus, we aimed at providing some information on the laboratory detection of Lassa from suspected cases in Nigeria.

Methods

This was a retrospective study of seasonal Lassa fever outbreaks data from 1,263 samples analyzed using Reverse Transcription-Polymerase Chain Reaction (RT-PCR) at the Virology Research Laboratory, College of Medicine, University of Lagos/Lagos University Teaching Hospital between year 2011 and 2017. Data were analyzed using the 21^st edition of SPSS statistical software (2015).

Results

The RT-PCR test confirmed the presence of Lassa in 112 (8.9%) comprising 61 (54.4%) males, 48 (42.9%) females and 3 (2.7%) individuals without gender information. Those aged between 18 and 49 years were mostly affected. There was a decline in the detection of Lassa from 4.7% in 2011/2012 to less than 1% by the 2014/2015. However, during the 2015/2016 and 2016/2017 seasons the detection rates increased to 10.4% and 15.1% respectively. The Northern region of Nigeria reported high confirmed cases of Lassa. The South Western region also witnessed an increased Lassa fever positivity rate of 13.4% of which Lagos and Ogun states being the focal state of Lassa activity in the region.

Conclusion

These established the need for heightening the continued surveillance for Lassa as well as the establishment of other testing facilities within these endemic regions for prompt diagnosis of Lassa fever.

Aeromedical Transfer of Patients with Viral Hemorrhagic Fever

For >40 years, the British Royal Air Force has maintained an aeromedical evacuation facility, the Deployable Air Isolator Team (DAIT), to transport patients with possible or confirmed highly infectious diseases to the United Kingdom. Since 2012, the DAIT, a joint Department of Health and Ministry of Defence asset, has successfully transferred 1 case-patient with Crimean-Congo hemorrhagic fever, 5 case-patients with Ebola virus disease, and 5 case-patients with high-risk Ebola virus exposure. Currently, no UK-published guidelines exist on how to transfer such patients. Here we describe the DAIT procedures from collection at point of illness or exposure to delivery into a dedicated specialist center. We provide illustrations of the challenges faced and, where appropriate, the enhancements made to the process over time.

Lack of Secondary Transmission of Ebola Virus from Healthcare Worker to 238 Contacts, United Kingdom, December 2014

In December 2014, Ebola virus disease (EVD) was diagnosed in a healthcare worker in the United Kingdom after the worker returned from an Ebola treatment center in Sierra Leone. The worker flew on 2 flights during the early stages of disease. Follow-up of 238 contacts showed no evidence of secondary transmission of Ebola virus.

A Gap Analysis Survey of US Aircraft Rescue and Fire Fighting (ARFF) Members to Determine Highly Infectious Disease Training and Education Needs

OBJECTIVE

Despite lessons learned from the recent Ebola epidemic, attempts to survey and determine non-health care worker, industry-specific needs to address highly infectious diseases have been minimal. The aircraft rescue and fire fighting (ARFF) industry is often overlooked in highly infectious disease training and education, even though it is critical to their field due to elevated occupational exposure risk during their operations.

METHODS

A 44-question gap analysis survey was distributed to the ARFF Working Group to determine where highly infectious education and training can be improved. In total, N=245 responses were initiated and collected. Descriptive statistics were generated utilizing Qualtrics Software Version 2016.17©.

RESULTS

Supervisors perceived Frontline respondents to be more willing and comfortable to encounter potential highly infectious disease scenarios than the Frontline indicated. More than one-third of respondents incorrectly marked transmission routes of viral hemorrhagic fevers. There were discrepancies in self-reports on the existence of highly infectious disease orientation and skills demonstration, employee resources, and personal protective equipment policies, with a range of 7.5%-24.0% more Supervisors than Frontline respondents marking activities as conducted.

CONCLUSIONS

There are deficits in highly infectious disease knowledge, skills, and abilities among ARFF members that must be addressed to enhance member safety, health, and well-being. (Disaster Med Public Health Preparedness. 2018;12:675-679).

Role of contact tracing in containing the 2014 Ebola outbreak: a review

BACKGROUND

The 2014 outbreak of Ebola virus disease which emerged in the month of March in the year 2014 in Guinea has been declared as a public health emergency of international concern.

OBJECTIVES

The objectives of the review article are to assess the role of contact tracing in the Ebola outbreak and to identify the challenges faced by the health workers while performing contact tracing.

METHODS

An extensive search of all materials related to the Ebola outbreak and contact tracing was carried out in PubMed, Medline, World Health Organization website and Google Scholar search engines. Keywords used in the search included Ebola virus disease, West-Africa, contact tracing, World Health Organization. Overall 60 articles were selected and included in the discussion.

RESULTS

Contact tracing is an important strategy in epidemiology and refers to the identification and diagnosis of those individuals who have come in contact with an infected person. It ultimately aims to reduce the time span required to detect and treat a case of an infectious disease and hence significantly minimize the risk of transmission to the subsequent susceptible individuals. In-fact, contact tracing continues to remain an important measure, as it aids the epidemiologist in containing the infection.

CONCLUSION

The strategy of contact tracing has a great potential to significantly reduce the incidence of cases of Ebola virus disease. However, its success is eventually determined by the level of trust between the community and the public health system and the quality of the diagnostic & treatment services.

Lassa fever: another threat from West Africa

Lassa fever, a zoonotic viral infection, is endemic in West Africa. The disease causes annual wide spread morbidity and mortality in Africa, and can be imported by travelers. Possible importation of Lassa fever and the potential for the use of Lassa virus as an agent of bioterrorism mandate clinicians in Israel and other countries to be vigilant and familiar with the basic characteristics of this disease. The article reviews the basis of this infection and the clinical management of patients with Lassa fever. Special emphasis is given to antiviral treatment and infection control.

International Air Travel to Ohio, USA, and the Impact on Malaria, Influenza, and Hepatitis A

The State of Ohio led the United States in measles in 2014, ostensibly related to international air travel (IAT), and ranked lower than 43 other states in infectious disease outbreak preparedness. We conducted a retrospective cohort study using surveillance data of the total Ohio population of 11 million from 2010 through 2014 with a nested case control of air travelers to determine the risk of malaria, seasonal influenza hospitalizations (IH), and hepatitis A (HA) disease related to international travel and to estimate the association with domestic enplanement. IAT appeared protective for HA and IH with a risk of 0.031 (.02-.04) but for malaria was 2.7 (2.07-3.62). Enplanement increased the risk for nonendemic M 3.5 (2.5-4.9) and for HA and IH 1.39 (1.34-1.44). IAT's ratio of relative risk (RRR) of malaria to HA and IH was 87.1 (55.8-136) greater than 219 times versus domestic enplanement which was protective for malaria at 0.397 (0.282-0.559). Malaria is correlated with IAT with cases increasing by 6.9 for every 10,000 passports issued.

Ebola virus disease in nonendemic countries

The 2014 West African outbreak of Ebola virus disease was unprecedented in its scale and has resulted in transmissions outside endemic countries. Clinicians in nonendemic countries will most likely face the disease in returning travelers, either among healthcare workers, expatriates, or visiting friends and relatives. Clinical suspicion for the disease must be heightened for travelers or contacts presenting with compatible clinical syndromes, and strict infection control measures must be promptly implemented to minimize the risk of secondary transmission within healthcare settings or in the community. We present a concise review on human filoviral disease with an emphasis on issues that are pertinent to clinicians practicing in nonendemic countries.

Public health response to commercial airline travel of a person with Ebola virus infection - United States, 2014

Before the current Ebola epidemic in West Africa, there were few documented cases of symptomatic Ebola patients traveling by commercial airline, and no evidence of transmission to passengers or crew members during airline travel. In July 2014 two persons with confirmed Ebola virus infection who were infected early in the Nigeria outbreak traveled by commercial airline while symptomatic, involving a total of four flights (two international flights and two Nigeria domestic flights). It is not clear what symptoms either of these two passengers experienced during flight; however, one collapsed in the airport shortly after landing, and the other was documented to have fever, vomiting, and diarrhea on the day the flight arrived. Neither infected passenger transmitted Ebola to other passengers or crew on these flights. In October 2014, another airline passenger, a U.S. health care worker who had traveled domestically on two commercial flights, was confirmed to have Ebola virus infection. Given that the time of onset of symptoms was uncertain, an Ebola airline contact investigation in the United States was conducted. In total, follow-up was conducted for 268 contacts in nine states, including all 247 passengers from both flights, 12 flight crew members, eight cleaning crew members, and one federal airport worker (81 of these contacts were documented in a report published previously). All contacts were accounted for by state and local jurisdictions and followed until completion of their 21-day incubation periods. No secondary cases of Ebola were identified in this investigation, confirming that transmission of Ebola during commercial air travel did not occur.

Potential for introduction of bat-borne zoonotic viruses into the EU: a review

Bat-borne viruses can pose a serious threat to human health, with examples including Nipah virus (NiV) in Bangladesh and Malaysia, and Marburg virus (MARV) in Africa. To date, significant human outbreaks of such viruses have not been reported in the European Union (EU). However, EU countries have strong historical links with many of the countries where NiV and MARV are present and a corresponding high volume of commercial trade and human travel, which poses a potential risk of introduction of these viruses into the EU. In assessing the risks of introduction of these bat-borne zoonotic viruses to the EU, it is important to consider the location and range of bat species known to be susceptible to infection, together with the virus prevalence, seasonality of viral pulses, duration of infection and titre of virus in different bat tissues. In this paper, we review the current scientific knowledge of all these factors, in relation to the introduction of NiV and MARV into the EU.