Understanding HCV / HIV Coinfection

What Is HIV?

The human immunodeficiency virus (HIV) belongs to a class of viruses called retroviruses.

Retroviruses are ribonucleic acid (RNA) viruses, and in order to replicate they must make a deoxyribonucleic acid (DNA) copy of their RNA. It is the DNA genes that allow the virus to replicate.

HIV belongs to a subgroup of retroviruses known as lentiviruses, or "slow" viruses.

The course of infection with these viruses is characterized by a long interval between initial infection and the onset of serious symptoms.

Infection typically begins when an HIV particle encounters a cell with a surface molecule called cluster designation 4 (CD4). Cells carrying this molecule are known as CD4 positive (CD4+) cells.

One or more of the virus' surface molecules binds tightly to CD4 molecule(s) on the cell's surface. 

The envelope (outer shell) of the virus and the cell membrane then fuse, infecting the target cell with the viral genetic material.

Although CD4+ T cells (specialized cells of the immune system) appear to be the main targets of HIV, other immune system cells with and without CD4 molecules on their surfaces are infected as well.

Among these are long-lived white blood cells (immune cells) called monocytes and macrophages, which apparently can harbor large quantities of the virus without being killed, thus acting as reservoirs of HIV.

How Is HIV Transmitted?

HIV is spread most commonly by having unprotected sex with an infected partner. The virus can enter the body through the lining of the vagina, vulva, penis, rectum, or mouth during sex.

Like hepatitis C, HIV also is spread through contact with infected blood.

HIV frequently is spread among injection drug users by the sharing of needles or syringes contaminated with very small quantities of blood from someone infected with the virus.

HIV can potentially infect anyone who:

• Shares drug needles or syringes
  
• Has sexual contact with an infected person without using a condom
  
• Has sexual contact with someone whose HIV status is unknown.

Having a sexually transmitted disease such as syphilis, genital herpes, chlamydial infection, gonorrhea, or bacterial vaginosis appears to make people more susceptible to getting HIV infection during sex with infected partners.

Women can transmit HIV to their babies during pregnancy or birth. Approximately one-quarter to one-third of all untreated pregnant women infected with HIV will pass the infection to their babies. 

However, if the mother takes the drug AZT during pregnancy, she can significantly reduce the chances that her baby will get infected with HIV.

HIV also can be spread to babies through the breast milk of mothers infected with the virus.

Although researchers have found HIV in the saliva of infected people, there is no evidence that the virus is spread by contact with saliva.

Scientists also have found no evidence that HIV is spread through sweat, tears, urine, or feces.

No one knows, however, whether so-called "deep" kissing, involving the exchange of large amounts of saliva or oral intercourse increase the risk of infection.

Studies of families of HIV-infected people have shown clearly that HIV is not spread through casual contact such as the sharing of food utensils, towels and bedding, swimming pools, telephones, or toilet seats.

HIV is not spread by biting insects such as mosquitoes or bedbugs.

What Is AIDS?

The term AIDS (Acquired Immunodeficiency Syndrome) is used to describe the advanced stages of HIV infection.

AIDS was first reported in the United States in 1981 and has since become a major worldwide epidemic.

The Center for Disease Control has developed criteria for diagnosing AIDS in a person who has HIV Infection, which include:

• A CD4 positive T cell count of less that 200/ml
  
• The presence of an "AIDS-defining condition" - an opportunistic infection or illness that generally does not affect healthy people

People with AIDS are particularly prone to developing various cancers, especially those caused by viruses such as Kaposi's sarcoma and cervical cancer, or cancers of the immune system known as lymphomas.

These cancers are usually more aggressive and difficult to treat in people with AIDS.

Hepatitis C is considered an opportunistic infection for people with HIV, but it is not an AIDS-defining condition.

How Long Does It Take For HIV to Cause AIDS?

Prior to 1996, scientists estimated that about half the people with HIV would develop AIDS within 10 years after becoming infected.

This time varied greatly from person to person and depended on many factors, including a person's health status and their health-related behaviors.

Since 1996, the introduction of powerful anti-retroviral therapies has dramatically changed the progression time between HIV infection and the development of AIDS.

There are also other medical treatments that can prevent or cure some of the opportunistic illnesses associated with AIDS, though the treatments do not cure AIDS itself.

Because of advances in drug therapies and other medical treatments, estimates of how quickly people will develop AIDS after HIV infection is being recalculated.

How Is HIV Infection Treated?

Proof of HIV infection is not necessarily a reason to begin treatment with medications. 

The time to start taking HIV medications depends on one's overall health, the amount of virus in the blood (viral load), and how well one's immune system is working.

Generally, a patient should consider treatment for HIV if:

• The patient is experiencing severe symptoms of HIV infection or has been diagnosed with AIDS
  
• The patient has a viral load is 55,000 copies/mL or more
  
• The patient's CD4 count is 200 cells/mm3 or less

Treatment may also be considered if the patient has a CD4 count between 200 and 350 cells/mm3, depending on the physician's assessment.

The decision to begin treatment for HIV is a serious one, because once treatment is started, it may be necessary to continue taking anti-HIV medications for life.

Although newer anti-HIV medications are easier to take, starting treatment usually requires a significant adjustment in lifestyle.

Some anti-HIV medications need to be taken several times a day at specific times and may require a change in meals and mealtimes.

In addition to their desired effects, anti-HIV medications may have negative side effects, some of which are serious.

If the virus is not suppressed completely, drug resistance can develop. Side effects and drug resistance may limit future treatment choices.

There are 20 anti-HIV medications approved by the U.S. Food and Drug Administration (FDA) for adults and adolescents.

The U.S. Department of Health and Human Services (DHHS) provides HIV treatment guidelines to doctors and patients.

These guidelines recommend a combination of three or more medications in a regimen called Highly Active Antiretroviral Therapy (HAART).

The guidelines list "preferred" HAART regimens. However, medication regimens should be tailored to each individual – there is no one "best" regimen.

For people taking HAART for the first time, the recommended regimens are:

• Sustiva + Epivir + (Retrovir or Viread or Zerit)

• Kaletra + Epivir + (Retrovir or Zerit)

Some people may benefit from a different regimen. Recommended alternative regimens are:

• Sustiva + Emtriva + (Retrovir or Viread or Zerit)
  
• Sustiva + Videx + (Epivir or Emtriva)
  
• Viramune + (Epivir or Emtriva) + (Retrovir or Zerit or Videx)
  
• Agenerase + low dose Norvir + (Epivir or Emtriva) + (Retrovir or Zerit)
  
• Reyataz + (Epivir or Emtriva) + (Retrovir or Zerit)
  
• Crixivan + (Epivir or Emtriva) + (Retrovir or Zerit)
  
• Crixivan + low dose Norvir + (Epivir or Emtriva) + (Retrovir or Zerit)
  
• Kaletra + Emtriva + (Retrovir or Zerit)
  
• Viracept + (Epivir or Emtriva) + (Retrovir or Zerit)
  
• (Fortovase or Invirase) + low dose Norvir + (Epivir or Emtriva) + (Retrovir or Zerit)

In general, taking only one or two drugs is not recommended because any decrease in viral load is almost always temporary without three or more drugs.

The exception is the recommendation for pregnant women, who may take Retrovir alone or with other drugs to reduce the risk of passing HIV to their infants.

Patients may experience negative side effects when taking HIV drugs.

Some of these side effects are serious, even life-threatening, and may require a change in drugs due to intolerable side effects.

Possible side effects of HAART include:

• Liver problems (hepatotoxicity)
  
• Diabetes
  
• Abnormal fat distribution (lipodystrophy syndrome)
  
• High cholesterol
  
• Increased bleeding in patients with hemophilia
  
• Decreased bone density
  
• Skin rash
  
• Pancreatitis (inflammation of the pancreas)
  
• Nerve problems

Side effects that might otherwise seem minor, such as fever, nausea, and fatigue, can indicate serious problems for people on HAART and should be discussed with the physician.

HAART has no significant effect on Hepatitis C infection.

However, people with HIV/HCV coinfection may be at increased risk for HAART-associated liver toxicity and should be closely monitored during antiretroviral therapy.

What Is HIV / HCV Coinfection?

The term "coinfection" describes a situation in which a person is infected with two (or more) diseases at the same time. 

HIV and HCV are transmitted by many of the same practices, and it's estimated that in the United States, between 200,000 and 300,000 people are coinfected with HIV/HCV.  Learn more about HCV transmission.

About 25 percent of Americans with HIV have HCV, and about 10 percent of people with HCV have HIV. 

Chronic HCV may be especially problematic for someone with HIV. 

Some studies have reported that people with co-infection have higher levels of hepatitis virus in their blood, more rapid progression of liver damage, and a greater rate of death due to hepatitis than people with only HCV infection.

Hepatitis B is the most common viral hepatitis infection in people with HIV, but HCV is more likely than any other form of hepatitis to result in chronic or long-term disease, liver failure, or death in coinfected people.

How Can Coinfection Be Prevented?

People who are infected with HCV infection can avoid HIV infection by avoiding behaviors that put a person at risk of infection, such as sharing needles and having unprotected sex. 

Similarly, people with HIV infection can avoid HCV infection by avoiding high-risk behaviors.

Routes of HCV transmission are described at length in the article How is Hepatitis C Transmitted from Person to Person?

As with HCV infection, people infected with HIV may have no obvious symptoms.

Therefore, there is no way of knowing with certainty whether a sexual partner is infected with HIV or HCV unless he or she has repeatedly tested negative for the virus and has not engaged in any risky behavior.

To avoid HIV infection, people should either abstain from having sex or use male latex condoms or female polyurethane condoms, which may offer partial protection, during oral, anal, or vaginal sex. Only water-based lubricants should be used with male latex condoms.

Although some laboratory evidence shows that spermicides can kill HIV, researchers have not found that these products can prevent a person from getting HIV.

Detecting HCV in HIV-Infected Persons

Antibodies are substances which are produced by the body in response to foreign invaders, such as bacteria and viruses.

Anti-HCV tests do not look for the presence of the hepatitis C virus directly, but instead search for antibodies that the body produces in response to the hepatitis C virus' presence.

Anti-HCV can be found in 7 out of 10 persons when symptoms begin (if symptoms appear at all) and in about 9 out of 10 persons within 3 months after symptoms begin.

However, because HIV can impair the activity of the immune system, people who are infected with HIV and HCV may not create enough HCV-antibodies to yield a "positive" anti-HCV test result.

This is more likely to happen with people who have a CD4 count of less than 100 /ml. 

In these cases, HCV detection may require direct assessment of the virus through polymerase chain reaction (PCR) tests.

Using the PCR tests, it is possible to confirm HCV infection within 1 to 2 weeks after being infected with the HCV virus.  Learn more about HCV testing.

How is HIV / HCV Coinfection Treated?

If the patient has not been previously treated for HIV, it may be preferable to treat the HCV infection first to decrease the probability of developing Highly Active Antiretroviral Therapy (HAART)-related liver disease, as HCV infection increases the probability of developing HAART-related hepatotoxicity.

If the patient is already being treated for HIV infection, they may be treated simultaneously treated with HAART and peginterferon/ribavirin combination therapy.

If the HAART regimen has resulted in hepatotoxicity in a coinfected patient, it may be necessary to reduce or discontinue HAART and initiate peginterferon/ribavirin therapy in an attempt to eradicate the hepatitis C virus and improve liver health.

If the patient's HCV infection can be successfully treated, it may be possible to resume full-dose HAART with a decreased risk of hepatotoxicity.  Learn more about HCV treatment.

HIV Information Resources

U.S. Government Resources

The Centers for Disease Control and Prevention (CDC) is the nation's primary HIV prevention agency.

• The CDC's Division of Adolescent and School Health (DASH) supports HIV prevention programs targeting youth.  DASH also publishes Guidelines for Effective School Health Education To Prevent the Spread of AIDS. 
  
• The CDC's Division of HIV/AIDS Prevention (DHAP) has two branches, one which manages HIV prevention programs and related funding, the other which supports the collection of information on the status of the epidemic.
  
• The CDC's Division of Sexually Transmitted Diseases supports efforts to prevent and control STDs, which are directly related to risk for HIV infection.
  
• The CDC's National Prevention Information Network serves as a clearinghouse for information related to HIV, STDs, and TB.

The Health Care Financing Administration (HCFA) offers information on preventing mother-to-child transmission and other useful information on women and pregnancy. 
 
The National Institutes of Health (NIH) and its Office of AIDS Research (OAR) are involved in the search for better treatments, a vaccine, and a cure.

The National Institute on Alcohol Abuse and Alcoholism offers HIV prevention interventions related to alcohol abuse or addiction.

The National Institute of Allergy and Infectious Diseases is involved in preventative HIV vaccine research, HIV prevention research, and a clinical HIV prevention trials network. Information is available through its Division of AIDS.

The National Institute on Drug Abuse addresses the interconnection of HIV/AIDS and drug abuse. Information is available through its Center on AIDS and Other Medical Consequences of Drug Abuse.

The National Institute of Mental Health provides research on behavioral HIV prevention. Information is available through its Office of AIDS Research.

The Substance Abuse and Mental Health Services Administration (SAMHSA) administers Federal drug treatment funding.

• SAMHSA's Center for Mental Health Services provides funding for the provision of mental health services to people living with HIV or at risk, as well as sponsoring research into the neuropsychiatric and psychosocial aspects of HIV/AIDS.
  
• SAMHSA's Center for Substance Abuse Prevention (CSAP) provides funding support for the prevention of substance abuse and related problems, including HIV infection.
  
• SAMHSA's Center for Substance Abuse Treatment provides support for drug addiction treatment, as well as research into special treatment issues for those living with HIV and AIDS.
  
• SAMHSA's National Clearinghouse for Alcohol and Drug Information offers a variety of publications on issues related to HIV/AIDS and drug use and abuse.

Healthfinder is a service of the Department of Health and Human Services that provides access to a broad array of health information, including a section on information related to HIV and AIDS.

Private Resources

AEGiS offers a comprehensive web site that provides information on the basics of HIV treatment, and links to a wide variety of organizations and media sources.
 
The Center for AIDS Prevention Studies (CAPS)  at the University of California at San Francisco helps disseminate information on HIV prevention, produces a wide variety of publications on HIV prevention programming and research, and assists in administering a Visiting Scholars Program in AIDS prevention research.

The HIV Infoweb is operated by the Justice Resource Institute's Health Division, with funding from the AIDS Bureau of the Massachusetts Department of Public Health . It offers links to an extensive array of HIV-related information.

The HIV InSite, operated by the University of California at San Francisco (UCSF), has sections on the medical, prevention, policy, and statistics related to HIV and AIDS.

The Body is an AIDS and HIV information resource web site operated by Body Health Resources Corporation. It offers chat rooms, references services, on-line libraries, and links to other information sources.

Source

How HIV Causes AIDS. National Institute of Allergy and Infectious Diseases. October 2001. http://www.niaid.nih.gov/factsheets/howhiv.htm

HIV Infection and AIDS: An Overview. National Institute of Allergy and Infectious Diseases. October 2003. http://www.niaid.nih.gov/factsheets/hivinf.htm

Hepatitis C and HIV Co-Infection: An Update.  U.S. Department of Health and
Human Services, Health Resources and Services Administration, HIV/AIDS Bureau. September, 2003.  http://hab.hrsa.gov/publications/september2003/

Frequently Asked Questions on HIV and AIDS.  Centers for Disease Control & Prevention, National Center for HIV, STD, and TB Prevention, Divisions of HIV/AIDS Prevention. October, 2003.  http://www.cdc.gov/hiv/pubs/faqs.htm

Frequently Asked Questions About Hepatitis C. Centers for Disease Control and Prevention, National Center for Infectious Diseases, Division of Viral Hepatitis.  October, 2004.  http://www.cdc.gov/ncidod/diseases/hepatitis/c/faq.htm

HIV and Its Treatment: What You Should Know. www.aidsinfo.nih.gov. U.S. Department of Health and Human Services, September, 2004.  http://aidsinfo.nih.gov/other/cbrochure/english/CBrochure_en.html

General Information on HIV and AIDS.  Office of National AIDS Policy, The White House.  http://www.whitehouse.gov/onap/links-general.html

Reviewed June 24, 2005 by V. J. Smith, RN, BSN, MA

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