H1N1 and HIV: Tips to Keep You Safe and Healthy

Summary

In March 2009 a new flu virus called H1N1 (also called swine flu) emerged in Mexico and quickly spread around the world. Now, as winter approaches, a time when flu infections are common, health authorities expect that H1N1 infections will surge in countries and regions in the northern hemisphere, including Canada, the United States, the European Union, Mexico and the Caribbean.

For many people, infection with the H1N1 virus causes mild-to-moderate flu symptoms that resolve in about a week. However, in a small proportion of people, infection with the H1N1 virus can cause serious complications that may require hospitalization. We are not yet certain about the factors that are responsible for these serious complications. However, based upon the best available evidence, people with weakened immune systems, including people with HIV, are expected to be at increased risk for complications arising from H1N1 infection.

In this CATIE News bulletin, we provide you with key information about H1N1, including tips on the prevention and treatment of H1N1 in adults with HIV.

Are People Living With HIV at Increased Risk for Complications From H1N1?

Like other influenza viruses, the H1N1 virus does not affect everyone in the same way. As H1N1 is an emerging infection, there is very little information about its specific impact on people living with HIV. Based on current understanding, here are some of the factors that may increase vulnerability to H1N1-related complications for people living with HIV.

People whose immune systems have been weakened by HIV are at increased risk for complications from influenza and possibly the H1N1 virus. This includes people with low CD4+ counts. Because many people are not diagnosed with HIV until the late stages of infection, there is a hidden population of people in this category who don't know they are HIV positive and are at increased risk for complications arising from influenza and H1N1 infection.

HIV positive people who have high CD4+ counts may also be at increased risk, even if they are taking anti-HIV drugs. Several studies have found that despite the use of anti-HIV drugs, people with HIV are still at increased risk for complications arising from seasonal flu, such as bacterial chest infections.

Some people with HIV can have other conditions that can weaken the immune system and may make them more vulnerable to seasonal flu, including the following:

• diabetes;
• cardiovascular disease;
• asthma;
• kidney dysfunction;
• having received a transplanted organ;
• pregnancy.

The conditions listed above may also increase the risk for complications from H1N1 infection.

Doctors in Canada, Mexico, the United States and elsewhere who have treated many people with H1N1 infection have found additional factors that appear to increase the risk of getting this infection:

• age between 20 and 49 years;
• being very overweight (having a body mass index greater than 30);
• having other health conditions.

Many experts recommend that HIV positive people be prioritized to receive the vaccine for H1N1 when it becomes available.

How H1N1 Is Spread?

This virus is transmitted in the same way seasonal flu is spread. When an infected person coughs or sneezes, they release a spray of tiny droplets of muc us containing flu viruses. If these droplets are inhaled by a person in close proximity, that person can also become infected. If the droplets land on surfaces such as counters, desks, door handles or doorknobs, they can be picked up by touch. Another person who touches these surfaces and then his or her nose, mouth or eyes can become infected. Also, flu viruses can survive on the skin, so shaking hands with an infected person can transmit these viruses. Flu viruses can survive outside the body on surfaces for up to 24 hours.

How Can I Protect Myself From Becoming Infected With H1N1?

1. General Tips

Here are some measures to help protect you from H1N1. These measures have generally been recommended by the Public Health Agency of Canada, the U.S. Centers for Disease Control and Prevention (CDC) and the European Centres for Disease Control:

• Wash your hands frequently and thoroughly with soap and warm water or use alcohol-based hand sanitizer. It is particularly important to wash your hands before eating and after returning home from public places.

• Cough or sneeze into your sleeve if no tissue is available.
• Avoid touching your eyes, nose and mouth. If you must do so, use a tissue. Dispose of the tissue after use.
• When possible, avoid contact with people who are ill with flu-like symptoms. If you are looking after a friend or family member who has H1N1, we pro vide some ways below to help reduce your risk of getting H1N1.
• Get the vaccine against seasonal flu. Even though H1N1 is likely to become a common virus, the seasonal flu virus will still be present. Seasonal flu infection can cause dangerous complications in HIV positive people. Note that the seasonal flu vaccine will not protect you from getting H1N1.
• Your immune system gets weaker when you are run down, so be sure to get a balance of sleep, rest and exercise. Reducing stress and eating a good diet are also helpful ways to stay healthy.

2. H1N1 Vaccine

Several vaccines against H1N1 are being tested in different parts of the world. While we don't have any specific information on how effective these vaccines will be for HIV positive people, it is expected, based on years of experience with other flu vaccines, that they will be as safe and effective as they are in HIV negative people. Federal, provincial, territorial and municipal health authorities will be creating a strategy for vaccination throughout Canada. Stay informed and aware of when the vaccine will become available in your region (see the Resource section at the end of this bulletin for information on how to stay informed). When the H1N1 vaccine does become available, talk to your doctor or nurse about getting this vaccine.

3. Prevention of H1N1 Infection With Antiviral Drugs

Antiviral drugs such as oseltamivir or zanamivir can, in some circumstances, be used t o help prevent H1N1 infection in people who are exposed to this virus but do not have symptoms of the flu. Using medicines in this way is called PEP—post-exposure prophylaxis. If you have been in close contact with a person who has been diagnosed with H1N1, speak to your doctor or nurse about the possibility of getting antiviral drugs to help protect you from H1N1 infection.

What Are the Signs and Symptoms of H1N1 Infection?

Because the signs and symptoms of H1N1 infection are very similar to seasonal flu, only your doctor or nurse can help diagnose the cause of your symptoms. Here are some of the symptoms associated with H1N1 infection:

• fever;
• cough;
• runny or stuffy nose;
• headache;
• muscle or bone pain;
• chills;
• fatigue;
• sore throat.

In some cases diarrhea and vomiting may also occur.

In extreme cases, the following signs/symptoms may also develop. If you experience the symptoms below, immediately contact your health care provider or dial 911:

• difficulty breathing or shortness of breath;
• pain or pressure in the chest or abdomen;
• sudden dizziness;
• disorientation or confusion;
• severe or persistent vomiting.

What Should I Do If I Have Symptoms of H1N1 Infection?

Because the signs and symptoms of H1N1 infection are very similar to those of seasonal flu, only your doctor or nurse can help diagnose the cause of your symptoms. If you experience flu-like symptoms, contact your doctor or nurse for advice. They will help decide what steps should be taken, such as whether you need antiviral medicines.

To avoid infecting other people with H1N1, stay at home as directed by your doctor or nurse.

If you experience severe flu-like symptoms, do not assume that the cause is H1N1. There are many other serious infections and conditions that can cause similar symptoms. Always seek medical advice for managing severe symptoms.

How Can I Care for Myself or Someone Else Who Has Been Infected With the H1N1 Virus?

For many people with H1N1 infection, health care providers will recommend home care and careful monitoring of symptoms. For this reason, it is important to be prepared to take care of yourself and others at home.

1. General Practices to Prevent the Spread of Infection

• Everyone in the household should take the precautions outlined in the section above: "How can I protect myself from becoming infected with H1N1?"
• Avoid sharing anything that may carry germs, such as towels, dishes or eating utensils. Keep the sick person's towels, dishes and utensils separate from the rest of the household.
• Clean common surfaces and shared items frequently, such as do or handles, tables, countertops, phones and remote controls.
• As much as possible, people infected with H1N1 should avoid close contact with others. This means keeping a distance of about two meters (or six feet), wearing a face mask or covering your mouth with a tissue. Consider having the person (or people) with H1N1 rest in a room by themselves, away from common areas of the home.
• People who have H1N1 infection should not have visitors until at least 24 hours after their fever has cleared. If fever-reducing medicines such as ibuprofen (Advil, Motrin) or acetaminophen (Tylenol) have been used, wait 24 hours after the time at which both the fever has ended and you have stopped taking anti-fever medication. Phone calls are safer than visiting.
• If your doctor or nurse agrees that you (or the sick person) can leave home for brief periods, wear a mask to avoid infecting others when you cough or sneeze.

2. Managing the Symptoms of H1N1

If your doctor or nurse has told you or someone in your household to stay at home because of H1N1 infection, here are some things to do to help manage illness and prevent the spread of infection:

• get plenty of rest;
• drink lots clear fluids such as water, juice, herbal teas or soup;
• avoid drinking alcohol, coffee, tea or energy-drinks, as they can dehydrate you;
• stay at home as directed by your doctor or nurs e;
• if you have been prescribed antiviral drugs for the flu, take them exactly as directed.

When your symptoms have cleared, talk to your doctor or nurse about returning to work or volunteer activities. In the days after your symptoms have cleared, your body will produce gradually decreasing amounts of H1N1. So once you are back at work or volunteering, it is important to keep washing your hands and practice safer coughing and sneezing behaviour so that you do not infect other people.

What Treatments Are Available for H1N1?

There are two antiviral drugs available on prescription that can be used to treat H1N1:

• oseltamivir (Tamiflu) -- available as tablets;
• zanamivir (Relenza) -- available as an inhaled powder.

These are the only medicines approved by authorities for the treatment of H1N1. They are most effective if used within 48 hours of the appearance of flu symptoms. Because the symptoms of seasonal flu are very similar to symptoms of H1N1, only your doctor or nurse can help diagnose the cause of your symptoms.

Usually treatment with these drugs lasts for five days. However, in cases of severe illness, particularly in people with weakened immune systems who have been hospitalized, some infectious disease specialists may prescribe longer courses or higher doses of treatment.

Here are some helpful tips to bear in mind when taking these antiviral drugs:

• Take anti-flu medicines exactly as prescribed by your doctor or nurse. If you do not take your medication on time every time, H1N1 may be become resistant to the medication. If H1N1 develops resistance, the medication will not longer work for you. Furthermore, you risk spreading this treatment-resistant H1N1 to someone else.
• Do not share your anti-flu medicine. If you think that a friend or loved one has H1N1, tell them to contact a doctor or nurse for help. It is important to be certain that the person has H1N1 before taking the medications. Many other serious infections and conditions can have symptoms similar to H1N1.
• Remember that oseltamivir and zanamivir are the only approved anti-flu medicines. If your doctor prescribes them for you, get them from a pharmacy, not over the Internet. Drugs ordered over the Internet may not be safe.
• No natural health products (vitamins, herbs or supplements) have been proven to be effective in preventing or treating H1N1.

More information about the treatment of H1N1 can be found here.

Safety of Antiviral Drugs

Oseltamivir and zanamivir have not been tested in clinical trials in pregnant women. However, doctors have had to treat pregnant women with these drugs so there is some information about their safety. The U.S. CDC20has noted that pregnant women who have H1N1 can be given these drugs. Zanamivir tends to concentrate in the lungs while oseltamivir can reach all tissues in the body. The CDC therefore recommends the use of oseltamivir in pregnant women with H1N1.

• Common side effects -- oseltamivir

Some people who used this drug reported such problems as nausea, vomiting and diarrhea. Taking oseltamivir with food may reduce nausea or vomiting. There are reports that Japanese children who have taken oseltamivir have developed neuro-psychiatric problems. However, this has not been generally reported in Japanese or non-Japanese adults.

• Common side effects -- zanamivir

This drug can irritate the lungs of people who have pre-existing lung conditions such as asthma. The U.S. CDC recommends that people with pre-existing lung conditions use oseltamivir instead of zanamivir. In some zanamivir users, diarrhea, nausea, headache and dizziness have occurred.

For more information about less common side effects of oseltamivir or zanamivir, speak to your pharmacist.

Drug Interactions

As H1N1 is an emerging infection, there is little information on interactions between anti-flu drugs and medicines used for the treatment of HIV infection. So far, no serious or life-threatening interactions between drugs used for the treatment of H1N1 and drugs used for the treatment of HIV have been documented.

Resources

Stay aware and informed by listening to or reading the news about H1N1 in your region. Additionally, as the winter outbreak of H1N1 unfolds, public health agencies will be posting updates. Here are some sites with reliable information:

Public Health Agency of Canada
British Columbia Centres for Disease Control
Ontario Ministry of Health and Long-term Care
Quebec Ministry of Health
U.S. Centers for Disease Control and Prevention
French Ministry of Health
World Health Organization

Acknowledgement

We thank Curtis Cooper, MD, from the Ottawa Hospital, for helpful discussion, research assistance and expert review.

References

1. Kunisaki KM, Janoff EN. Influenza in immunosuppressed populations: a review of infectio n frequency, morbidity, mortality, and vaccine responses. Lancet Infectious Diseases. 2009 Aug;9(8):493-504.
2. Grayson ML, Melvani S, Druce J, et al. Antiviral efficacy of soap and water hand washing and alcohol-based hand-rub solutions against live H1N1 influenza A on the hands of human volunteers. In: Program and abstracts of the 49th Interscience Conference on Antimicrobial Agents and Chemotherapy, San Francisco, California, September 12-15, 2009. Abstract K-1796.
3. Hoffmann G, Funk C, Fowler S, et al. Non-clinical pharmacokinetics of oseltamivir and oseltamivir carboxylate in the central nervous system. Antimicrobial Agents and Chemotherapy. 2009; in press.
4. Rello J, Rodriguez A, Ibanez P, et al. Intensive care adult patients with severe respiratory failure caused by Influenza A (H1N1)v in Spain. Critical Care. 2009 Sep 11;13(5):R148.
5. Rebbapragada A, Drews S, Green K, et al. A comparison of clinical features and outcomes of hospitalization due to seasonal and pandemic influenza A (H1N1). In: Program and abstracts of the 49th Interscience Conference on Antimicrobial Agents and Chemotherapy, San Francisco, California, September 12-15, 2009. Abstract V-1047j.
6. Lye D, Chow A, Tan A, et al. Oseltamivir therapy and viral shedding in pandemic (H1N1) 2009. In: Program and abstracts of the 49th Interscience Conference on Antimicrobial Agents and Chemotherapy, San Francisco, California, September 12-15, 2009. Abstract V-1269c.
7. D e Serres G, Rouleau I, Hamelin ME, et al. Shedding of novel 2009 pandemic H1N1 (nH1N1) virus at one week post illness onset. In: Program and abstracts of the 49th Interscience Conference on Antimicrobial Agents and Chemotherapy, San Francisco, California, September 12-15, 2009. Abstract K-1918a.
8. Ruiz-Palacios GM. Ground zero: the emergence of a pandemic? In: Program and abstracts of the 49th Interscience Conference on Antimicrobial Agents and Chemotherapy, San Francisco, California, September 12-15, 2009. Abstract 1081.
9. H1N1 (swine flu): general information. Centers for Disease Control and Prevention. Available at: www.cdc.gov/h1n1flu/general_info.htm. [Accessed September 18, 2009].
10. The expert panel on influenza and personal protective respiratory equipment. Influenza transmission and the role of personal protective respiratory equipment: an assessment of the evidence. Council of Canadian Academies. December 19, 2007. Available at: www.scienceadvice.ca/influenza.html. [Accessed September 18, 2009].
11. Neumann G, Noda T, Kawaoka Y. Emergence and pandemic potential of swine-origin H1N1 influenza virus. Nature. 2009 Jun 18;459(7249):931-9.
12. Perez-Padilla R, de la Rosa-Zamboni D, Ponce de Leon S, et al. Pneumonia and respiratory failure from swine-origin influenza A (H1N1) in Mexico. New England Journal of Medicine. 2009 Aug 13;361(7):680-9.
13. Chowell G, Bertozzi SM, Colchero MA, et al. Severe respiratory disease concurrent with the circulation of H1N1 influenza. New England Journal of Medicine. 2009 Aug 13; 361(7):674-9.