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Infection Prevention & Control Challenges in the 2014-15 West African Ebola OutbreakAdriano G DuseHead: Division of Clinical Microbiology and Infectious Diseases & Director: Hospital Epidemiology & Infection Control Services
School of Pathology of the NHLS and University of the Witwatersrand, Johannesburg, South Africa
Family: Filoviridae Single stranded RNA viruses(filum – Latin – thread)
Ebola virus activity over time (1976 – 2002)
Year Virus Geographic Location Human Deaths
Cases CFR
1976 SUDV Juba, Maridi, Nzara and Tembura, SUDAN 151 284 53%
1976 EBOV Yambuku, ZAIRE 280 318 88%
1977 EBOV Bonduni, ZAIRE 1 1 100%
1979 SUDV Nzara, SUDAN 22 34 65%
1988 EBOV Porton Down, UNITED KINGDOM (laboratory accident) 0 1 0%
1994 TAFV Tai National Park, CŎTE D’IVOIRE 0 1 0%
1994 – 1995 EBOV Woleu-Ntem and Ogooué-Ivindo Provinces, GABON 32 52 62%
1995 EBOV Kikwit, ZAIRE 245 317 77%
1996 EBOV Mayibout , GABON 21 31 68%
1996 EBOV Sergiyev Posad, RUSSIA (laboratory accident) 1 1 100%
1996 - 1997 EBOV Ogooué-Ivindo Province, GABON; Cuvette-Ouest Department, REPUBLIC OF THE CONGO
46 62 74%
2000 – 2001 SUDV Gulu, Mbarara and Masindi Districts, UGANDA 224 425 53%
2001 – 2002 EBOV Ogooué-Ivindo Province, GABON; Cuvette-Ouest Department, REPUBLIC OF THE CONGO
97 124 78%
Ebola virus activity over time (2002 – 2014)
Year Virus Geographic Location Human Deaths
Cases CFR
2002 EBOV Ogooué-Ivindo Province, GABON; Cuvette-Ouest Department, REPUBLIC OF THE CONGO
10 11 91%
2002 – 2003 EBOV Cuvette-Ouest Department, REPUBLIC OF THE CONGO; Ogooué-Ivindo Province, GABON
128 143 90%
2003- 2004 EBOV Cuvette-Ouest Department, REPUBLIC OF THE CONGO 29 35 83%
2004 EBOV Koitsovo, RUSSIA (laboratory accident) 1 1 100%
2004 SUDV Yambio County, SUDAN 7 17 41%
2005 EBOV Cuvette-Ouest Department, REPUBLIC OF THE CONGO 9 11 82%
2007 EBOV Kasai Occidental Province, DEMOCRATIC REPUBLIC OF THE CONGO 186 264 71%
2007 – 2008 BDBV Bundibugyo District, UGANDA 39 116 34%
2008 – 2009 EBOV Kasai Occidental Province, DEMOCRATIC REPUBLIC OF THE CONGO 15 32 47%
2011 SUDV Luweero District, UGANDA 1 1 100%
2012 SUDV Kibaale District, WESTERN UGANDA 17 24 71%
2012 BDBV Orientale Province, DEMOCRATIC REPUBLIC OF THE CONGO 34 62 54%
2014 EBOV GUINEA, LIBERIA, SIERRA LEONE, SENEGAL, MALI
2014 -15 EBOV SPAIN, UNITED STATES, ETC …
Increasing frequency of outbreaks since 1990
Possible reasons:
• Better surveillance and capability to rapidly diagnose and characterize filovirus infections
• Spread among wild non-human primates and other animals
• Complexity of epidemiology and ecology
• Human encroachment on natural ecosystems
• Increased human exposure
• Proximity of outbreaks to larger cities and human movement
Transmission
Transmission
• Direct contact with blood and bodily fluids (saliva, breast milk, stool tears, etc.) during acute phase illness; convalescence: breast milk and semen
• No evidence of risk from casual skin contact with asymptomatic people
• Environmental contamination and fomites do not pose a significant risk if recommended IPC practices applied
Infect Dis. 2007 Nov 15;196 Suppl 2: S142-7.Assessment of the risk of Ebola virus transmission from bodily fluids and fomites. Bausch DG, Towner JS, Dowell SF, Kaducu F, Lukwiya M, Sanchez A, Nichol ST, Ksiazek TG, Rollin PE.
Transmission, risk factors and infectiousness
• Risk factors
• hunting, slaughtering, butchering
• community and hospital care of EHF victims
• preparation of bodies and attending funerals
• EBOV ID is thought to be very low (1-10 virions)
• Estimated number of secondary cases generated by an index case in the absence of control interventions (R0) for Ebola in 2 epidemics 1.3 – 1.8
Infection rates
• The number of people that one sick person will infect, on average and in the absence of an effective control intervention, is called R0
R0 More contagious
1 > 2 infection rate
Hepatitis CEbola (?)
1 > 4 infection rate
HIVSARS
1 > 10 infection rate
Mumps
1 > 18 infection rate
Measles
Epidemiological characteristics of the 2014 West African Ebola outbreak
Summary of Ebola outbreak characteristics in West Africa
Term Definition Current estimates
Reproductive number (R0): Number of healthy people one sick individual infects over the course of his/her illness.
Guinea: 1.71Liberia: 1.83Sierra Leone: 2.02
Serial interval: Time between consecutive people falling ill in a chain of transmission.
15.3 days
Incubation period: Amount of time passed between a person becoming exposed to Ebola and when they start to show symptoms of the disease.
11.4 days
Doubling time: Time taken for the number of sick individuals to double. Guinea: 15.7 daysLiberia: 23.6 daysSierra Leone: 30.2 days
Confirmed case fatality rate: Number of people who die of confirmed Ebola infection. Guinea: 70.7%Liberia: 72.3%Sierra Leone: 69.0%
Unconfirmed case fatality rate: Number of people who die of suspected but not confirmed Ebola infection.
Guinea: 13%Liberia: 58%Sierra Leone: 35%
Source: Doi:10.1371/journal.pntd.0003652.t002
EVD transmission: what is known and what is not …
• Limited data on how viral genomics affect phenotype/pathotype, patient VLs & epidemiological features of EBOV (Makona) strain
• Further study:
•Role of aerosol (large droplets/small particles close to patients) transmission
•Role on environmental contamination & fomite transmission
•Degree to which minimally or mildly ill persons transmit infection
•How long clinically relevant infection persists or persistence of Ebolavirus during convalescence
•Role of ‘superspreading events’ play in transmission dynamics
•Whether strain differences or repeated serial passage in outbreak settings can impact virus transmission
Source: MBio 2015 Feb 19;6(2):e00137. doi:10.1128/mBio.00137-15
Persistence of Ebola virus and EVD in convalescence
•Reported EVD post acute infection sequelae
•2 weeks – 2 months: arthralgias, parotitis, orchitis, convulsions, psychotic behaviour, neck stiffness, skin sloughing, hair loss, vision loss/uveitis, hearing loss
•Anecdotally, >1 yr: abdominal pain, hearing loss, ocular deficits, bleeding, psychological symptoms, sleep disturbances, malaise, impotence, severe headaches and functional limitations
•Retrospective cohort study of long-term sequelae after Bundibugyo EVD noted that such sequelae persist for > 2 years post infection
Source: Clark et al: www.thelancet.com/infection Vol 35 Aug 2015
Persistence of Ebola virus and EVD in convalescence
• Largest number reported of survivors in current W African 2014-15 outbreak
• Detection of viable EBOV in aqueous humor in patient with anterior (then pan-) uveitis 14 weeks after onset of EVD & 9 weeks after clearance of viraemia
• Samples of conjunctivae and tears tested negative for EBOV supporting previous studies that there is probably no risk of spread of infection with casual contact
• Pauline Cafferkey:
• 39 y old nurse from Glasgow, contracted EVD in Sierra Leone in Dec 2014, seemingly recovering for many months
• Admitted to hospital in Oct 2015 after feeling unwell & flown to Royal Free Hospital in London after testing positive with EVD
• Viral meningitis, isolation of EBOV from CSF
• Question: can survivors spread Ebola? Unlikely: fluids in eye and brain not exchanged
Source: NEJM 2015;372:25
Sexual transmission of EVD in convalescence
• Ebola Virus founds in all sites & fluids associated with sexual activity; persistence in convalescence occurs in breast milk (up to 15d after onset), rectum, vagina secretions (up to 33d after onset) & semen (at least 101 days after onset)
• Pilot study involving 100 survivors at different times after EVD recovery:
• Declining persistence of EV RNA persistence with increasing months since onset of EVD; however 11 of 43 (26%) of people had a positive specimen obtained 7-9 months after onset. Results of 1 participant who had specimen obtained at 10 months were indeterminate
Source: Deen et al NEJM 2015 Oct 14 [Epub ahead of print]
Sexual transmission of EVD in convalescence
•Recent evidence of EV transmission from survivor to a Liberian woman 6 month after recovery: EV RNA found as late as 155 days after clearance of disease in semen from a convalescent survivor.
•Finding EV RNA from semen ≠ infectivity; further testing being carried out to look for active virus in semen
•Sexual transmission not source of many new EVD cases, but may be a source of late EVD cases ?
•Late cases => WHO proposed heightened surveillance: 90 days beyond 42 days of no further EVD. Mate et al study suggests that period should be extended ?
Source: Mate et al NEJM.org. Oct 154 2015
Ebola West Africa 20(13)14 - 2015
Ebola W Africa
• 6 December 2013: 2-year old infected in Gueckedou, Guinea; start of largest documented Ebola epidemic
• Public health impact far greater than case counts• Crippling of an already weakened health sector
• Significant impact of other endemic (e.g. malaria) diseases & associated mortality
• Substantial economic losses for entire sub-region
• Social disruption
As at 26 June 2014:
Guinea: 396 cases, 280
deaths
Liberia: 63 cases, 41 deaths
Sierra Leone: 176 cases, 46
deaths
Case fatality rate: 43%-68%
The border …
Confirmed, probable and suspected EVD cases in Guinea, Liberia and Sierra Leone at 25 October 2015
Country Case definition Cumulative cases Cases in past 21 days Cumulative deaths
Guinea
Confirmed 3350 3 2082
Probable 453 * 453
Suspected 3 * ‡
Total 3806 3 2535
Liberia **
Confirmed 3151 6 - 0 ‡ 2
Probable 1879 * - * ‡ ‡
Suspected 5636 ‡ - * ‡ ‡
Total 10666 6 - 0 4806 2
Sierra Leone
Confirmed 8704 0 3589
Probable 287 * 208
Suspected 5070 * 158
Total 14061 0 3955
Total
Confirmed 15211 6 ‡
Probable 2619 * ‡
Suspected 10709 * ‡
Total 28539 6 11298
•Not reported due to high proportion of probable and suspected cases that are reclassified ‡ Data not available ** Cases reported before 9 May 2015 are shaded blue
Source: World Health Organisation Ebola Situation Report 28 October 2015
Cumulative cases
Country
By sex *(per 100 000 population)
By age group ‡(per 100 000 population)
Male Female 0-14 years 15 – 44 years 45+ years
Guinea1598(29)
1744(32)
534(11)
1903(41)
861(55)
Liberia Ꞩ1911(96)
1838(93)
561(33)
2060(121)
703(132)
Sierra Leone4823(169)
5118(176)
1992(82)
5636(218)
2140(290)
* Excludes cases for which data on sex are not available ‡ Excludes cases for which data on age are not available Ꞩ Data are until 9 May 2015
Cumulative number of confirmed cases by sex & age group in Guinea, Liberia & Sierra Leone at 25 October 2015
Source: World Health Organisation Ebola Situation Report 28 October 2015
Human Population Movement
Confirmed, probable and suspected EVD cases worldwide as at 18 October 2015
Factors resulting in emergence of Ebola in W Africa
• Environmental/ecological
• Demographics & population movement
• Sociological
Environmental
• Pathogen spillover
•Putative reservoir: fruit bats (Hypsignathus monstrosus, Myonycteris torquata, Eidolon helvum)
•Migration
• ?Movement of bat colonies from Central Africa to W Africa
•Conditions did not occur previously
•Transmission to wildlife species
• Seasonal triggers
•Local & regional weather patterns
•Deforestation and land-use change
• Guinean forest surrounding outbreak area is a major biodiversity spot containing one quarter of all African mammalian fauna
• Dramatic human encroachment into these areas with cumulative forest loss estimated to be between 83%-86%
Doi:10.1371/journal.pntd.0003652.t002
Historical & demographic factors
• Historical civil war & conflict – poverty, poor health infrastructure, poor education, large population movements and displacements
• Dramatic population growth in the sub-region
• Human mobility
• In W African region migration rates exceed movement in the rest of the world by > 7-fold
• Increased pressure on food production, including access to bush meat (in Liberia, a critical source of protein exceeding 75% of country’s meat use)
Screening
Infection Prevention and Control (IPC)
Infection Control
Strategy for controlling Ebola outbreaks
Infection Prevention and Control (IPC)
• Main strategies: triage, early identification of cases, testing, isolation, supportive management; tracing and monitoring of contacts
• Engaging community and religious leaders to understand how burial teams could adapt IPC practices without offending cultural and religious sensitivities
• Nosocomial transmission amplification among HCWs
• Failure to strictly adhere to barrier precautions: contact with infectious blood, (other) tissues, excreta and other body fluids
• Sharps and splash injuries
• Mechanical aerosolization of infectious particles
IPC: Health Worker Infections
Country Cases Deaths
Guinea 196 100
Liberia* 378 192
Sierra Leone 307 221 ‡
Total 881 513
* Data are until 9 May 2015 ‡ Data as of 17 February 2015
Ebola virus disease infections in healthcare workers in Guinea, Liberia and Sierra Leone at 25 October 2015
World Health Organisation Ebola Situation Report 28 October 2015
Health worker Ebola infections in Guinea, Liberia and Sierra Leone
Health worker Ebola infections in Guinea, Liberia and Sierra Leone
• Period: 1 January 2014 to 31 March 2015
• ‘Health worker’ very broad category; not just clinicians & nurses; also lab staff, drivers, cleaners, burial teams, janitors & community-based workers
– Depending on category, 21-32X more likely to be infected cf. general population
– Over this period, HCWs accounted for 3.9% (815/20955) of all confirmed & probable patients
– Nurses, nurse aids account for > 50% (373/718), followed by ‘medics’
• Difficulties in establishing where infections were contracted: at triage?; community?; working in healthcare facilities in other centres, OPDs?; and homes?
WHO/EVD/SDS/REPORT/2015.1
Health worker Ebola infections in Guinea, Liberia and Sierra Leone
Source: WHO/EVD/SDS/REPORT/2015.1
Health worker Ebola infections in Guinea, Liberia and Sierra Leone
WHO/EVD/SDS/REPORT/2015.1
Determinants of health worker infections
• Deficiencies in administrative controls
• Lack of or inappropriate point of care risk assessment
• Problems with patient flows and zoning
• Lack of IPC policies and staff
• Lack of PPE supplies and training
• Lack of engineering and environmental controls
• Inadequate isolation and barriers
• Problems with PPE
• Defective practices/exposure at the point of care
• Transmission outside patient care setting
• Poor employment conditions and social determinants
IPC: Personal Protective Equipment (PPE)
PPE training
Effectiveness of PPE for HCWs Caring for Patients with Filovirus Disease
• PPE recommendations & protocols differ across organizations responding to the outbreak, including WHO & MSF
– Different PPE item combinations & protocols confusing if no grounding in IPC
• In Oct 2014 WHO issued recommendations on PPE for use by HCWs managing patients with known or suspected filovirus disease
• Important is both effectiveness of PPE combinations in preventing EVD transmission as well as levels of dexterity & discomfort
• 30 observational studies of PPE of which 11 addressed filoviral disease; none compared different approaches to personal protection or different types of PPE.
– Only 1 designed to evaluate PPE use
– All had reporting and/or methodological deficiencies; none addressed comfort & dexterity
Source: PLOS ONE Ι DOI: 10.1371/journal.pone.0140290 October 9, 2015
Effectiveness of PPE for HCWs Caring for Patients with Filovirus Disease
• Conclusions:
• Insufficient evidence to draw conclusions on comparative effectiveness of different types of PPE & protocols; additional research urgently needed
• Future research in materials science & engineering: comfort, heat, breathability, visibility, minimization of viral contamination especially during doffing
• Other factors, not within scope of this review, e.g. hand washing & environmental cleaning are critical elements in IPC
Source: ONE Ι DOI: 10.1371/journal.pone.0140290 October 9, 2015
Virus Transfer from PPE to Healthcare Employees’ Skin and Clothing
• 10 volunteers (9 right-handed and 1 left-handed)
• PPE contaminated with suspension of bacteriophage MS2 (non-enveloped, non-pathogenic RNA v) and GloGerm beads that fluoresce under UV light
• Sites of contamination: front and back shoulder of gown, right side of N95 respirator, upper right front of goggles, palm of dominant hand
• Hands, items of PPE, and scrubs worn underneath sampled for virus
Source: Casanova et al, Emerg Infect Dis 2008;14(8):1291-3
Frequency and levels of viral contamination of selected sites, virus transfer study, 2007*
% Volunteers who
transferred virus to site (N = 10)
Mean viral titer recovered
from site (log10 MPN)*
% Contaminated sites with visible tracer (N = 10)
Non-dominant glove 80 2.2 10
Right hand (skin) 90 2.4 20
Left hand (skin) 70 1.8 0
Scrub shirt 100 3.2 10
Scrub pants 75 † 2.1 0
Face 0 - -
*MPN, most probable number; –, not measured; †, N = 8.
Source: Casanova et al, Emerg Infect Dis 2008;14(8):1291-3
PPE and HCW safety: conclusions
• Current CDC algorithm is insufficient to protect HCWs from contamination during PPE removal
• Other protocols exist that require double-gloving, hand disinfection between every step of PPE removal, actions derived from surgical protocols for PPE removal, and even PPE impregnated with an antimicrobial agent is available
• Casanova et al recommend that all other PPE protocols should be tested using same methodology to identify and minimize risks to HCWs
Source: Casanova et al, Emerg Infect Dis 2008;14(8):1291-3
Obstacles to the Outbreak Response
Fear!
Rumours!
Panic!!
Media (social and conventional)
Denial!
Obstacles to the epidemic response
•Poverty
•Poor infection prevention and control practices
•Poor healthcare delivery
•Fear
•Anger
•Behavioral, religious & cultural diversity
Burials and culture
• Understanding Muslim burials• Engagement with Imams, Muftis and other influential community
leaders
• Understanding how last rites are performed on the recently deceased (washing and preparation of the body)
• Identifying infection risks and looking at ways to overcome these
• In Islam, 3 conditions exist where body preparation processes are curtailed: (i) persons who have died in a lake or water, (ii) burn/accident victims, (iii) ‘other’ – subject to permission of the highest ranking authority in a region
50
Burial and culture: dignity in burial
Obstacles to the epidemic response
• Denial: ‘There is no such thing as Ebola’
• Misconceptions about causal etiology communicated by community leaders e.g. Traditional Healers - attribution to witchcraft
• Stigma of survivors, the infected or thought to be infected
Stigma
• EVD stigmatization including HCWs, suspected cases and survivors
•Negative impact on disease reporting & health-seeking behaviors
•Both HCWs & survivors: rejection by communities, ostracization, burning of belongings, stoning
Challenges inc. controversial public health messages
• ‘Do not eat bush game’
• Social distancing; no handshaking
• Closure of markets (economic implications) and recreational areas e.g. bars and discotheques
• Vaccination and treatment
• Draconian quarantine imposition on returning volunteer workers
• Stopping of flights; border closures; travel bans
• Closure/reduction in mining operations (force majeur) - serious economic consequences for the W African sub-region
Economic implications: West Africa (and beyond)
Bull*** our government is spreading it to reduce the population. Remember satan has
control over governments. Also our own government worships satan.
Wow look at all this Bible prophecy coming true this tell me that it's time for all of us to give our lives to JESUS right now and be covered by his blood we all
need to repent of all our sins and ask JESUS to forgive us
This virus has the same symptoms with ZOMBIFICATION which was a
voodoo practices; Zombie is defined as corpse said to be revived by
witchcraft
Americans have vaccine and probably they invent this virus during cald war and use on who else than poor africans !! but they dont give vaccine to anyone except of this 2 or 3 persons from USA few weeks ago who are healed while others (africans especially)you
will be died !!
Ebola is the lifeline for the American economy
that has already tumbled over the edge. The virus can be more powerful
than any bomb; especially if America
holds the "cure".
America is going to release ebola in America and blame it on isis. New 9/11 and population control.
Our elites are particularly into genocide in Africa. You must not think that all white
men wish to kill all black people. Its really all about
oligarchs and elite Jew pigs.
I say drop a bomb on them they a third world country destroy
their kings a boom we get Africa and we can sell it
It comes to me as if the doctors dont even care about Ebola victims. Once their infected, they’re no longer human, treat
them like scum and leave them for dead as they slowly rot on the inside and die alone never to see their family again
The blame and misconceptions
The blame and misconceptions
Hostility & suspicion: stoning of healthcare teams and survivors
Host
Environ-ment
Microbe
Individual human behavior and movement
Host susceptibility
EBOV
Geo-climatic, geographical and ecological
Socio-culturalTraditional beliefs,
Traditional healers and Witchdoctors,
Religion,Burial practices
Suspicion and misconceptions
Political Low-socioeconomic
Conclusions
• Geographic origin, population mobility and social circumstances favoured the largest Ebola outbreak described to date
• Multi-scaled early warning and surveillance efforts needed locally, nationally, regionally and globally
• National, traditional and community leaders must be involved
• National and community ownership crucial for sustainability
• Further research needed: ecology, transmission, prevention & cure
THANK YOU