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Common Viral infections in Africa: Surveillance for HAI Resp infections

4th Nov 2014, 5th ICAN/ICAZ conference

Division of Global Disease Detection and Emergency Response

Center for Global Health

Dr. Linus Ndegwa, MPHE, HCS,SHEA AmbInfection Control, Manager

Global Disease Detection-GDD

Centers for Disease Control and Prevention-Kenya

Influenza

Influenza: serious respiratory illness, can be debilitating and cause complications leading to hospitalization and death

Most affected: very young, persons with underlying medical conditions and elderly

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Global impact of influenza

Globally, seasonal influenza causes 3-5 million cases of severe illness and 300,000-500,000 deaths

Past pandemic influenza associated with millions of deaths

1918: “Spanish Flu” 1957: “Asian Flu” 1968: “Hong Kong Flu”

20-40 million deaths 1-4 million deaths 1-4 million deaths 3

Influenza virus

Influenza A and B viruses are of epidemiological interest in humans

Types B and C limited to humans

Type A viruses are more virulent and affect many species

Antigenic determinants of influenza A and B are: Haemagglutinin (HA) and Neuraminidase (NA) glycoproteins

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Influenza Virus

Hemagglutinin It is a glycoprotein Receptor that binds host cells

inducing penetration of the virus

Antigenic sites at the outer surface

Antibodies to HA are protective

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Influenza Virus

Neuraminidase (NA): 9 known

Helps release virions from cells

Antibody to NA can help modify disease severity

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Influenza Virus

Antigenic drift and shift:

arises from mutations in the antigenic sites reducing biding of neutralizing antibodies

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Influenza Virus

Antigenic shift (genome re-assortment)

arises when the HA is exchanged in a virus e.g. H1 replaced by H5

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Influenza virus

Influenza A viruses subtypes:

– 16 HA (H1-H17)

– 9 NA (N1-N9) subtypes

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Epidemiology of Influenza

Virological Pattern: Northern Hemisphere

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Epidemiology of Influenza

Virological Pattern: Southern Hemisphere

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Epidemiology of InfluenzaVirological Pattern: Kenya

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Burden of seasonal influenza in Kenya

Influenza circulates at least 11 months per year Influenza detected in : 10-12% of respiratory hospitalizations annually, >30% during periods of peak circulation 8.7% of rHAI in 30months surveillance

Highest rates in children < 6 months Influenza-associated hospitalizations in children

<5 years are 3-7 times higher than in the United States, despite less care-seeking

persons with HIV more likely to spread influenza in their homes

Current Epidemic and Pandemic Threats!

Pathogen Date of first report

Laboratory-confirmedcases

Deaths Case Fatality Proportion

Date of last reportedcase

A(H5N1) January, 2004 668 393 58.8% Sep, 2014

A(H7N9) February, 2013

453 175 38.6% Aug, 2014

Middle East Respiratory SyndromeCoronavirus

June, 2012 885 319 36% Oct, 2014

Transmission

Influenza viruses transmitted via air droplets Close contact (up to 3-6 feet) is required for transmission Transmission may also occur through:

– direct skin-to-skin contact – indirect contact with respiratory secretions – Touching contaminated surfaces then touching the eyes,

nose or mouth)

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Transmission

Incubation period 1-2 days

Individuals may spread influenza virus from up to 2 days before to 5 days after onset of symptoms

Children can spread the virus for 10 days or longer

Immunocompromized persons also tend to shed the virus longer

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Clinical Presentation

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Complications of Human Influenza

Pneumonia– primary influenza pneumonia the most severe– secondary bacterial pneumonia being the most common – mixed viral and bacterial pneumonia frequently occurs

Secondary bacterial pneumonia is most commonly caused by :– Streptococcus pneumoniae, – Staphylococcus aureus– Haemophilus influenzae

Chronic cardiac and pulmonary disease predispose Reye’s syndrome in children with Flu B

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Influenza Prevention and Control

Non pharmacologic– Surveillance – Isolation and quarantine– Social distancing– Respiratory protection– Cough and sneeze etiquette– Hand washing

Pharmacologic– Vaccination– Antiviral drugs

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Historically no routine

surveillance for HAIs

Kenyan hospitals:

– Patient overcrowding

– Inadequate hand hygiene

We set up surveillance

for respiratory HAI started

Infection Control and Prevention in Kenya

Objectives

To document respiratory HAIs occurring on selected wards in 3 Kenyan hospitals

To identify the viruses causing respiratory HAIs

Surveillance sites Prospective surveillance

Site: 3 selected hospitals

– Kenyatta National hospital: 1800 beds

– Mbagathi District hospital: 200 beds

Apr 1, 2010

Wards

– Medical

– Pediatric

– The ICU

Surveillance Sites

Hospitals

Case Definition: Respiratory HAIs

Inclusion Criteria:

– Patients admitted >3 calendar days• Admit date: Day 1

– New onset fever/hypothermia

• (≥38°C or <35°C)

• No fever/hypothermia in past 3 days

– New onset of cough or sore throat

Written consent

Laboratory tests

Nasopharyngeal/oropharyngeal swabs collected

Samples tested by real time RT-PCR

Samples collected and tested for:

– Influenza A & B

– Adenovirus

– Respiratory syncytial virus (RSV)

– Human metapneumovirus (HMPV)

– Parainfluenza virus 1, 2 and 3. (PIV 1,2,3)

Laboratory tests

Specimens positive for influenza A were subtyped

– Seasonal H1N1

– Pandemic H1N1

– H5N1

– H3N2

Surveilance

Surveillance officers at each site

Review of in-patients records for new onset of signs and symptoms

Approved by:

– Kenya Medical Research institute ERC

– CDC- Atlanta IRB

Results

Sampling for Respiratory HAI

18545 cases of fever or hypothermia

documented

1255 occurred >3days after admission

with no fever in past 3days

379 with respiratory symptoms

concurrent with fever/hypothermia

In 17 instances, patient

refused swabbing or no

consent obtained112 Swabbed

Respiratory HAIs : Demographics

Conclusion

Surveillance showed that rHAI occurred consistently during the 30 months period

Rates are similar to those in other developing nations

Most cases were positive for at least 1 viral pathogen

Infection control should be strengthened

Continued HAI surveillance critical to monitor the burden of HAIs and impact of control measures

Acknowledgements

ICAN president: Prof. Shaheen

ICAN president: prof Val

Founder and president OASIS: Prof SolomKin

Kenyatta National Hospital

Mbagathi District Referral Hospital

New Nyanza Provincial Hospital

Ministry of Health – Kenya

CDC – Kenya

Div. Healthcare Quality Promotion

CDC – Atlanta

The findings and conclusions in this presentation/report are those of the

author and do not necessarily represent the views of the Centers for

Disease Control and Prevention

Are there any questions?

ikf7@cdc.gov

Protect your patients. Protect yourself. Protect your family.

Asante Sana (Thank you)