H1N1 influenza

16th October 2009

Interim Guidance for Clinical Management and Laboratory Investigations of Patients with Pandemic Influenza A (H1N1) Virus Infection in a Setting with Sustained Community Transmission
This document provides interim guidance for medical officers who provide care for patients and contacts with pandemic influenza A (H1N1) virus infection (previously referred to as swine-origin influenza virus). These interim guidelines were adopted at a special expert meeting held at the Office of the DDG PHS, Ministry of Health chaired by the Deputy Director General Public Health Services on 16th October 2009 which met to discuss new strategies to minimize the impact of the disease with the onset of community transmission.
Therefore the following key strategies have been adopted:

1. All patients with suspected H1N1 influenza attending to hospitals will be screened to assess their illness and only patients with severe or progressive symptoms will be admitted to hospitals for laboratory diagnosis and treatment with anti virals.
2. Those with mild illness would be managed as out patients with supportive medication and proper advice.
3. Medical Research Institute (MRI) will continue to process the samples for laboratory diagnosis on requests by physicians attending to hospitalized patients.

Case definitions
With the onset of possible sustained community transmission in the country, case definition of a suspected H1N1 Influenza case could be considered even without epidemiological risk factors of overseas travel history and contact history.

Following case definitions must be adhered to in management and reporting of cases.
Suspected case:
An Individual presenting with acute febrile respiratory illness (fever >38 °C) with the spectrum of disease from influenza-like illness (cough, sore throat, shortness of breath) to pneumonia

With or without any of the following epidemiological risk factors:
• Close contact to a suspected/probable/confirmed/ case of novel influenza A(H1N1) virus infection while the case was ill within the last 7 days
• Recent travel to an area where there are confirmed cases of novel influenza A (H1N1) within the last 7 days
(Close contact, for the purpose of this document, is defined as having cared for or lived with a person who is a confirmed, probable or suspected case of novel influenza A (H1N1), or having been in a setting where there was a high likelihood of contact with respiratory droplets and/or body fluids of such a person. Examples of close contact include kissing or embracing, sharing eating or drinking utensils, physical examination, or any other contact between persons likely to result in exposure to respiratory droplets. Close contact typically does not include activities such as walking by an infected person or sitting across from a symptomatic patient in a waiting room or office).
Probable case:
An individual with an influenza test that is positive for influenza A, but is unsubtypable by reagents used to detect seasonal influenza virus infection

Confirmed case:
An individual with laboratory confirmed novel influenza A (H1N1) virus infection by one or more of the following tests:
• real-time (RT) PCR
• viral culture
• four-fold rise in novel influenza A(H1N1) virus specific neutralizing antibodies.
Most healthy persons who develop an illness consistent with influenza or those who appear to be recovering from influenza do not need hospitalization or anti viral medication. However those in the following groups need to be assessed for hospitalization and treatment based on the clinical judgment of the treating physician.
• People with more severe illness eg evidence of lower respiratory tract infection
• Those with suspected influenza and deteriorating clinical condition
• People with suspected or confirmed influenza who are at higher risk for complications
o Children younger than 2 years old
o Adults 65 years and older
o Pregnant women
o People with certain chronic medical or immunosuppressive conditions such as chronic lung (including asthma), cardiovascular (excluding hypertension), renal, hepatic, haematological (including sickle cell disesae), metabolic disorders (including diabetes mellitus), immunosuppression, including that caused by medications or by HIV, those with disorders that can compromise respiratory function e.g spinal cord injuries, seizure disorders
o People younger than 19 years of age who are receiving long-term aspirin therapy

However it should be emphasized that clinicians may treat some persons who are not in a high risk group based on their clinical judgment. In addition, they also may decide that treatment is not needed for some who are in a high risk group based on their clinical judgment.
1. Measures to be taken at Out Patient Department (OPD) Setting (Government or Private Hospital)
With the infection spreading in the community widely, there may be a large influx of patients to hospitals and the hospital authorities should be geared to handle this situation. All Out Patient Departments in government and private hospitals should display a sign board directing persons who are harbouring symptoms/signs suggestive of Pandemic Influenza A/H1N1 infection to a special counter/room where a medical officer with appropriate infection control measures would assess them to decide on the course of management (if he/she would be admitted).

• Provide a disposable/surgical face mask to the patient
• Make arrangements to provide him/her with medical attention and to assess the patient to decide on the course of management
• If it has been decided to treat the patient as an outpatient, provide him/her with necessary supportive therapy and medication (eg antipyretics, anti histamines, rehydration etc) before sending home
• Give necessary advise to the patient to avoid contact with others and also to limit the movements of his/her family members who would be his/her close contacts
• If it has been decided to admit the patient for treatment and if the institution is not a sentinel hospital identified under the Pandemic Influenza Preparedness Programme (Annex II), make arrangements to obtain the contact details of the patient and to transfer patient with necessary infection control measures to the closest sentinel hospital for sample collection for laboratory diagnosis, isolation and clinical management.
• The referring hospital should contact the sentinel hospital to which the patient is being directed to and alert on his/her arrival there
• If the institution is a sentinel hospital, the hospital authorities could manage the patient in its own isolation ward. However attending clinicians must decide on anti viral therapy/laboratory investigations for the patient based on their clinical judgment and given guidelines.

2. Measures to be taken at a General Practitioner’s (GP) Setting/ Specialist in Private Sector
If a patient presents to a GP/Specialist in the private sector the following actions should be taken.
• Assess the patient carefully to decide on the course of management
• Provide a disposable/surgical face mask to the patient
• If it has been decided not to hospitalize the patient and to treat him/her as an outpatient in the present setting, provide him/her with necessary supportive therapy and medication (eg antipyretics, anti histamines, rehydration etc) before sending home
• Give necessary advice to the patient to stay away from work/school/crowded places and to take bed rest, plenty of liquids, good diet and seek medical attention if symptoms worsen.
• If it was decided to admit the patient, he/she could be managed in a private hospital where treatment facilities are available or he/she could be directed to the closest sentinel hospital for clinical management
• The GP/Specialist should contact the hospital to which the patient is being directed to and alert on his/her arrival there
3. Management of cases in hospital setting
The recommended antiviral Oseltamivir is available mainly through identified sentinel hospitals under the Pandemic Influenza Preparedness Programme (Annex II), other government hospitals up to Base Hospital level and also in the private sector in a limited capacity. Anti viral therapy will be essentially limited for hospitalized patients.

This disease is known to be mostly self limiting and most patients ill with this disease will recover without complications. Two groups of patients should be treated with this anti viral therapy.
Those are:
1. Patients who do not belong to a high risk category but who have severe or progressive illness and those who have symptoms of lower respiratory tract illness or clinical deterioration
2. Patients who are at higher risk for complications (those belonging to the above mentioned groups) with severe or progressive illness
Physicians may also decide not to treat some people in these groups and/or treat people who are not in these groups based on their clinical judgment.

Once the decision to administer antiviral treatment is made, treatment with oseltamivir should be initiated as soon as possible. The treating clinician may use his or her discretion in commencing antiviral therapy based on his/her clinical judgment. Treatment may be discontinued if the laboratory tests become negative.

Treatment

Adult: Oseltamivir 75mg twice a day for 5 days

Oseltamivir is not recommended to be given to children less than one year old.

Dosage for children over 1 year of age: Oseltamivir to be given twice a day for 5 days, dosage based on child’s weight.
 15 kg → 30 mg twice daily
15 - 23 kg → 45 mg twice daily
23 - 40 kg → 60 mg twice daily
> 40 kg → 75 mg twice daily

Infection Control and Waste Management

Infection control and waste disposal should be along the same specifications cited for avian influenza in the circulars earlier issued on the subject, Gen. Circular No.02-164/2005 ‘Guidelines for the Preparedness and Response to an Avian Influenza Pandemic Threat’ dated 30/11/2005 and Gen. Circular No.01-19/2006 ‘Joint Circular on Guidelines on Collection and Transport of Specimens’ dated 15/03/2006 (available at http://www.epid.gov.lk/Disease%20Situations.htm).

4. Management of Contacts and Chemoprophylaxis with Antivirals
For antiviral chemoprophylaxis of pandemic (H1N1) influenza virus infection, oseltamivir is recommended. The duration of antiviral chemoprophylaxis post-exposure is 10 days after the last known exposure to pandemic (H1N1) influenza.
Antiviral chemoprophylaxis with oseltamivir can be considered for health care personnel or public health workers who have had a recognized, unprotected close contact exposure to a person with novel (H1N1) influenza virus infection (confirmed, probable, or suspected) during that person’s infectious period.
Adult Dosage for Prophylaxis

Oseltamivir 75mg once daily for 10 days

Paediatric Dosage for Prophylaxis

To be given once daily for 7 days, based on child’s weight:
 15 kg → 30 mg daily
15 - 23 kg → 45 mg daily
23 - 40 kg → 60 mg daily
40 kg → 75 mg daily

5. Guidance for Laboratory Diagnosis for Confirmation of Cases
Facilities for testing for pandemic H1N1 influenza are only available at the Medical Research Institute (MRI). Since the resources for this activity is limited and MRI would only process a limited number of samples, strict criteria would apply on laboratory investigations.
1. Samples will be collected only from patients with severe symptoms who have been admitted and will be based the attending physician’s clinical judgment
• Appropriate laboratory specimens (please refer general circular 01-19/2006 ‘Joint Circular on Guidelines on Collection and Transport of Specimens’ dated 15/03/2006, available at http://www.epid.gov.lk/Disease%20Situations.htm) from these patients should be sent to Medical Research Institute (MRI) for laboratory diagnosis using the special request form developed by the MRI for this purpose. A special authorization from the head of the institution or an authorizing officer will be required by the MRI for all requests from private hospitals.
• MRI would be open to receive specimen for 24 hours. It would direct the test results within 24 hours to the respective hospital and to the Epidemiology Unit by telephone/fax.
• Suspected cases presenting to the GPs should be directed to the sentinel hospitals or private hospitals where treatment facilities are available for admission and laboratory investigations if it is warranted.
• For patients in the private sector who requires laboratory testing, initial screening through conventional PCR should be carried out (if facilities are available) ideally before sending specimen to MRI for RT PCR.

Annex II

List of Hospitals selected as Sentinel Sites for Pandemic Influenza Preparedness

1. GH Ampara
2. TH Karapitiya
3. GH Matara
4. LRH
5. IDH
6. NHSL
7. TH Kalubowila
8. TH Peradeniya
9. TH Ratnapura
10. TH Kurunegala
11. SJGH
12. BH Vavunia
13. BH Nuwara Eliya
14. TH Badulla
15. TH Anuradhapura
16. BH Polonnaruwa
17. TH Ragama
18. BH Chilaw
19. TH Batticoloa
20. TH Jaffna