Patient information: Avoiding infections in pregnancy

INTRODUCTION

Like all adults and children, pregnant women are at risk for developing viral and bacterial infections. Infections are a particular concern during pregnancy since some infections are more severe in pregnant women or increase the risk of harm to the fetus or newborn. Fortunately, you can take steps to decrease the chance of developing a potentially harmful illness during pregnancy.

AVOIDING EXPOSURE TO INFECTIOUS DISEASES DURING PREGNANCY

Pregnant women should consider measures to avoid exposure to infectious agents known to cause problems during pregnancy.

Hygiene — Good hygiene practices, such as frequent hand washing and avoiding contact with another person's saliva through shared foods, drinks, or utensils, can lessen your chances of becoming infected with potentially harmful illnesses.

Good hygiene is particularly important for pregnant women who work or live with young children, as in day care centers or schools. Some potentially harmful infections, such as cytomegalovirus, are more prevalent in young children.

Hand washing — Hand washing is an essential and very effective way to prevent the spread of infection. Hands should be wet with water and plain or antimicrobial soap and rubbed together for 15 to 30 seconds. Pay special attention to the fingernails, between the fingers, and the wrists. Rinse the hands thoroughly and dry with a single use towel.

Alcohol-based hand rubs are a good alternative for disinfecting hands if a sink is not available. Spread hand rubs over the entire surface of hands, fingers, and wrists until dry. Hand rubs are available as a liquid or wipe in small, portable sizes that are easy to carry in a pocket or handbag. When a sink is available, visibly soiled hands should be washed with soap and water.

Hands should be washed before and after preparing food and eating, after going to the bathroom, after changing a diaper or assisting a child with toileting, after handling garbage or dirty laundry, after touching animals or pets, and after gardening.

Food precautions — Food precautions have been recommended for all consumers by the Food Safety and Inspection Services (www.fsis.usda.gov) and the Centers for Disease Control and Prevention. These food precautions are detailed in a separate topic. (See "Patient information: Food poisoning (food-borne illness)", in the section on food poisoning prevention).

Insect borne illnesses — Pregnant women should take precautions that reduce the risk of acquiring mosquito-borne infections (eg, West Nile virus in the United States, malaria in some tropical countries). (See "Patient information: West Nile virus infection".)

Mosquito bites can be prevented through use of protective clothing, avoiding the outdoors when mosquitoes are most active (dawn and dusk), and use of DEET-based insect repellents. DEET is the most effective insect repellent currently available. Products with 10 to 35 percent DEET are adequate in most circumstances. Used as recommended, DEET has an excellent safety record. Pregnant and breastfeeding women can use DEET.

Updated information regarding mosquito repellents is available from the CDC at www.cdc.gov/ncidod/dvbid/westnile/RepellentUpdates.htm.

Sexually transmitted infections — Pregnant women should be aware that your risk of being infected with a sexually transmitted infection may increase if you have multiple sexual partners or if your partner has multiple partners. Unless you are absolutely certain that your partner has no other sexual partners and is free of sexually transmitted infections, you should ask your partner to wear a condom. (See "Patient information: Genital herpes" and "Patient information: Gonorrhea" and "Patient information: Chlamydia" and "Patient information: Condyloma (genital warts) in women".)

Travel — Avoiding travel to high risk locations is one way to minimize the chances of becoming infected with certain infectious diseases. In some parts of the world, polio, yellow fever, and malaria are still common. Women who are planning international travel during pregnancy should consult with a travel clinic about the safety of the planned destination. (See "Patient information: General travel advice".)

Immunizations for family — Children and other family household members should be up to date with their immunizations; this decreases a pregnant woman's risk of exposure to infections during pregnancy. Vaccine safety during pregnancy is discussed separately. (See "Patient information: Immunizations and pregnancy".)

Animal borne illnesses — Women who are pregnant or planning pregnancy should avoid contact with all rodents. Precautions about handling pets and laboratory animals should be discussed with a healthcare provider. (See "Patient information: Animal bites".)

INFECTIONS

Several infectious diseases can cause problems in pregnancy. Currently, these infections cannot be prevented with a vaccine. These infections are best avoided by practicing good hygiene and avoiding direct contact with infected individuals (although this may be difficult in some cases).

Parvovirus B19 (Fifth disease) — Parvovirus B19 infection, also known as "fifth disease," is a common childhood viral infection. Since the infection is common during childhood, 40 to 60 percent of women are already immune by the time they become pregnant.

In adults, parvovirus causes mild to severe symptoms, including joint pain, fatigue, and body aches. A rash may appear on the face, trunk, arms, and legs (picture 1A-B). The rash on the face can be intensely red as though the person had been slapped (this is called a "slapped cheek" appearance). The illness generally resolves without treatment.

It is difficult to avoid contact with people who are infected with parvovirus because the infection is common in the community and an infected person is contagious before symptoms develop. Frequent hand washing and avoiding shared food or drinks can help to prevent infection.

If you are exposed to parvovirus during pregnancy and you have not been tested previously, a blood test for parvovirus is recommended. A positive test soon after exposure means that you had the infection in the past and are now immune, so the fetus is protected from infection. If blood testing is initially negative, it may be repeated three to four weeks later to confirm that you have not developed the infection. (See "Parvovirus B19 infection during pregnancy".)

Pregnant women who become infected with parvovirus are monitored closely for signs of complications. Rarely, parvovirus can cause a miscarriage, a low fetal blood count, or fetal heart problems.

Cytomegalovirus infection (CMV) — Cytomegalovirus (CMV) is a virus that is transmitted by sexual contact or other close contact with an infected person's saliva, urine, or other body fluids. Being infected with CMV causes few or no problems in people with a healthy immune system. However, the virus can cause serious problems for infants of mothers who are infected during pregnancy. (See "Cytomegalovirus infection in pregnancy".)

Approximately 60 percent of women in the United States have been exposed to CMV before becoming pregnant. However, the virus can reactivate at any time, even years after the initial exposure (similar to herpes). The risk of becoming infected with CMV for the first time is higher for pregnant women who live with young children or work in day care centers.

Currently, there is no way to prevent CMV infection. Medications to treat CMV in newborns are currently being studied. Vaccines against CMV are also being tested, but are not yet available. Good hygiene practices, especially hand washing, are encouraged to decrease the chances of developing CMV infection during pregnancy. Guidelines from the Centers for Disease Control and Prevention (CDC) are available at www.cdc.gov/ncidod/diseases/cmv.htm, and include the following:

• Practice good personal hygiene throughout pregnancy, especially hand washing with soap and water after contact with diapers or saliva (particularly with a child who is in day care). Do not share food or utensils.
• Women who develop a low-grade fever, malaise, enlarged lymph nodes, sore throat, and fatigue during pregnancy should be evaluated for CMV infection. The evaluation usually involves a blood test.
• Women with an active CMV infection may pass the virus to their infant through breastmilk. However, the benefits of breastfeeding outweigh the minimal risk of acquiring CMV from breastmilk. (See "Patient information: Deciding to breastfeed".)

Toxoplasmosis — Toxoplasmosis is a parasitic illness that usually causes no symptoms. However, toxoplasmosis can affect the fetus if a woman becomes infected during pregnancy. House cats can carry the toxoplasmosis parasite in their feces, but the more common way to become infected is by consuming undercooked meat. (See "Toxoplasmosis and pregnancy".)

Pregnant women should avoid eating rare and uncooked meat. While it is not clear that changing a cat litter box is a major risk for becoming infected with toxoplasmosis, it is probably reasonable for pregnant women to have someone else change the box or to wear gloves and then wash hands carefully afterwards. It is also important to wear gloves while gardening and to wash hands after working in the yard since the soil can be contaminated by cat feces.

Listeria — Listeria is a bacterial infection that can cause fetal death, premature birth, or newborn infection. It can be passed from an infected mother to her fetus through the blood. Signs and symptoms of Listeria include fever, chills, and back pain; a nonspecific flu-like illness is the most common symptom. (See "Treatment, prognosis, and prevention of Listeria monocytogenes infection".)

Most people who become infected with Listeria have eaten food that is contaminated. Contaminated foods do not appear rotten or spoiled and it is not possible to know, based upon appearance or smell, if a food is safe. For this reason, women who are pregnant are advised to avoid foods that could contain Listeria (see 'Food precautions' above.

IMMUNIZATIONS

Immunizations safety during pregnancy is discussed separately. (See "Patient information: Immunizations and pregnancy".)

TREATMENT OF INFECTIONS DURING PREGNANCY

The safety and availability of treatment for infection in pregnant women depends upon the type of infection and risk of harm (from the treatment or the infection) to the woman and her fetus. Pregnant women and their families are advised to discuss any concerns about infections or treatments with a healthcare provider.

WHERE TO GET MORE INFORMATION

Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two people are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.

This discussion will be updated as needed every four months on our web site (www.uptodate.com/patients). Additional topics as well as selected discussions written for healthcare professionals are also available for those who would like more detailed information.

Some of the most pertinent include:

Patient Level Information:
Patient information: A guide to pregnancy
Patient information: Food poisoning (food-borne illness)
Patient information: West Nile virus infection
Patient information: Genital herpes
Patient information: Gonorrhea
Patient information: Chlamydia
Patient information: Condyloma (genital warts) in women
Patient information: General travel advice
Patient information: Immunizations and pregnancy
Patient information: Animal bites
Patient information: Deciding to breastfeed

Professional Level Information:
Chemoprophylaxis for the prevention of neonatal group B streptococcal disease
Clinical manifestations and diagnosis of Listeria monocytogenes infection
Group B streptococcal infection in pregnant women
Group B streptococcus: Virulence factors and pathogenic mechanisms
Immunization of pregnant women
Intraamniotic infection
Overview of TORCH infections
Prevention of arthropod and insect bites: Repellents and other measures
Rubella in pregnancy
Toxoplasmosis and pregnancy
Treatment, prognosis, and prevention of Listeria monocytogenes infection
Varicella-zoster virus infection in pregnancy
Parvovirus B19 infection during pregnancy
Cytomegalovirus infection in pregnancy
Patient information: A guide to pregnancy

A number of web sites have information about medical problems and treatments, although it can be difficult to know which sites are reputable. Information provided by the National Institutes of Health, national medical societies and some other well-established organizations are often reliable sources of information, although the frequency with which they are updated is variable.

• National Library of Medicine

      (www.nlm.nih.gov/medlineplus/healthtopics.html)

• Centers for Disease Control and Prevention (CDC)

      Toll-free: (800) 311-3435
      (www.cdc.gov)

• Infectious Diseases Society of America

      (www.idsociety.org)

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