Listeria monocytogenes is a type of bacteria that is found in soil, animals and intestinal normal flora. You can get listeria from contaminated foods such as dairy products made from unpasteurised milk and vacuum-packed, raw-pickled fish. Listeria also grows at refrigeration temperatures and can survive for years.

  • Listeriosis can cross the placental barrier and infect the placenta, amniotic fluid and foetus.
  • The baby may become infected during delivery when passing through the birth canal. In such cases, the disease may appear days if not weeks after delivery.
  • A listeria infection does not always pass from mother to foetus.


A listeriosis infection during pregnancy may cause miscarriage, stillbirth, premature delivery or infection of the newborn. The newborn baby may develop meningitis days or weeks after delivery. However, it is also possible to recover from listeriosis and for the pregnancy to continue normally.


In pregnant women, listeriosis typically causes flu-like symptoms. Other symptoms include back pain, diarrhoea and vomiting.

Listeriosis is treated with antibiotics, but the effectiveness of treatment can not be guaranteed. During pregnancy, treatment is usually started when listeriosis is first suspected to prevent the infection from spreading to the foetus or newborn baby.


  • Avoid unpasteurised dairy products, soft cheeses, vacuum-packed, cold-smoked and raw-pickled fish products, fish roe and pates.
  • Do not use food that is past its 'use by' date, because listeria also grows at refrigeration temperatures.
  • Heat frozen vegetables before serving them.
  • Be sure to cook meat thoroughly at over 70°C.
  • Store raw and uncooked foods away from cooked products.


The risk of complicated malaria is highest in pregnant women, and therefore travelling to malaria risk areas while pregnant is not recommended. In pregnant women, malaria may cause severe anaemia and increase the risk of miscarriage. A chronic infection together with maternal anaemia may increase the risk of foetal growth retardation and low birth weight, and an acute infection may contribute to the risk of premature delivery.

The risk of stillbirth increases and the risk of toxaemia of pregnancy may be increased. During the acute stage, infected red blood cells accumulate in the placenta and may disturb placental function by blocking capillary circulation. As a result, oxygen supply to the foetus is reduced and the risk of placental abruption (premature detachment of the placenta) increases. As a result of maternal malaria, the newborn baby may develop congenital malaria.


Typically, the incubation period of malaria is 7 to 30 days, but it can last for months or even years. Taking antimalarial medications may lengthen the incubation period.

Typical symptoms include a cyclic occurrence of shivers followed by fever and profuse sweating as the fever subsides. During the primary attack, symptoms may comprise a consistently high fever associated with stomach symptoms, violent diarrhoea, respiratory symptoms, and symptoms of the central nervous system including delirium and reduced consciousness.

If your temperature rises after you have been abroad, schedule an appointment with your physician without delay. A finger-prick test yielding results in a couple of hours will confirm whether or not you have contracted malaria.



It is important to take preventive measures against malaria. Use prophylactics to prevent infection by a mosquito infected with malaria and to prevent symptomatic malaria.

  • If travelling to a high risk area cannot be avoided, a prophylactic drug regime is selected based on the drug resistance of the malarial parasite in the target area.
  • Wear lightly coloured, long-sleeve trousers and shirts after sunset.
  • Keep the windows and doors to your sleeping quarters closed.
  • Sleep under a mosquito net treated with Permethrin, and make sure you tuck it in under your mattress.
  • Spray rooms with insecticide.

Taking antimalarial drugs does not guarantee 100% protection against infection. The most appropriate antimalarial drug regime is selected based on the area you intend to visit and the current recommendations.

Doxycycline is not recommended for pregnant women, although it may be prescribed under certain circumstances. As for other antimalarial drugs, no indications of an increased risk of harmful effects on the foetus have been detected. There is limited experience in using some antimalarial drugs during pregnancy and their safety has not been confirmed. In addition to the travel destination, other factors to consider when selecting the appropriate prophylactic regime include the stage of pregnancy and possible risks associated with medications. Drug resistance in malarial parasites adds to the challenge of selecting effective prophylactic treatment.

The same drugs are used in the prevention and treatment of malaria. Pregnant women with malaria should be optimally treated and appropriate drugs administered without delay.

Slapped cheek syndrome (fifth disease)

Slapped cheek syndrome is also known as Erythema infectiosum or fifth disease. It is an infection caused by parvovirus B19. Parvovirus B19 is spread by airborne droplet infection, and its incubation period is approximately 7 days (6 to 16 days).

Symptoms typically include flushed cheeks, rash on the arms, legs and body, and joint symptoms. However, half of those infected have no symptoms at all and by the time the rash appears, the disease is no longer infectious. There are no specific medications for slapped cheek syndrome.

A parvovirus infection during pregnancy may be passed to the foetus and infect the foetal red blood cell precursors.

  • Infection in early pregnancy may cause miscarriage. However, there is no evidence that infection with parvovirus B19 would cause birth defects.
  • If you become infected between weeks 12 to 24 of your pregnancy, the disease may cause anaemia and myocarditis resulting in foetal hydrops (excess fluid in foetal tissues). Some babies can recover from foetal hydrops.
  • If you have been exposed, a blood sample is taken and checked for antibodies. Usually, the test is repeated after a couple of weeks to confirm or exclude a recent infection. 
  • If you become infected after 24 weeks of pregnancy, the disease does not pose any significant threat to the developing baby.

Risk groups include day care personnel who have not had slapped cheek syndrome. If transferring to another group or task is not possible, your physician may consider prescribing sick leave until the epidemic has passed. Once you've been infected you have lifelong immunity.


Cytomegalovirus (CMV) infection

 Cytomegalovirus (CMV) is a member of the herpes virus group, and the most common cause of congenital infection. CMV is spread by bodily fluids such as saliva and blood. The incubation period of a primary infection is usually several weeks (typically 6 to 8 weeks).
  • Symptoms include fever, fatigue, sweating, muscle pains, coughing, nausea and swollen glands. However, in many cases the infection does not cause any symptoms.
  • Primary maternal infection poses the greatest threat to the unborn baby. Developmental disorders are most often associated with an infection during the first 16 weeks of pregnancy.
  • With recurring CMV (a previously inactive CMV infection is reactivated) and re-infection with a different strain of CMV, the risk of passing the cytomegalovirus to the foetus is small.
  • The virus passes into breast milk and is naturally transmitted to the newborn. However, the risk of contracting an infection from breast milk is considered small, and mothers are generally encouraged to breastfeed their babies, unless the baby is very premature.

Preventive measures include good hand hygiene and avoiding secretions. However, sometimes the risk is associated with working in facilities for the developmentally disabled, where close physical contact with patients potentially carrying the virus cannot be avoided.


Toxoplasma gondii is a parasite which can be carried by many mammals, but the main host is the cat.

  • Contracting toxoplasma during pregnancy increases the risk of miscarriage, stillbirth, premature birth and congenital toxoplasmosis.
  • The risk increases if the infection is contracted in early pregnancy. A maternal infection may lead to severe foetal infection.
  • Primary maternal infection poses the greatest threat to the unborn baby. A recurring infection is not as dangerous.

Toxoplasmosis is caused by the parasite Toxoplasma gondii that is found in cat faeces, undercooked or raw meat and dirty vegetables. In most cases, toxoplasmosis does not cause any symptoms and is therefore often not diagnosed. Possible symptoms include fever, fatigue and sweating. The incubation period is on average 10 to 14 days, and recovery takes a couple of weeks.


  • Be sure to cook meat thoroughly.
  • Never touch cat faeces. Wear gloves when changing a cat's litter tray and wash your hands thoroughly afterwards.
  • Wash fruit and vegetables thoroughly before serving them. Peeling is strongly recommended.
  • Wash your hands thoroughly after gardening or sitting by a sand box.
  • Avoid drinking unpasteurised milk and eating raw eggs.
  • Avoid travelling to a high-risk region.


Chickenpox is a common childhood illness caused by the varicella zoster virus (VZV).

In adults, the symptoms of chickenpox may be severe, and adults are more likely to experience complications such as pneumonia which may require intensive care. The incubation period is 7 to 21 days.

Symptoms include an itchy rash with spots first appearing on the chest and belly, fever and headache.

Chickenpox is highly contagious and easily spread by airborne droplets. The majority of the population catch chickenpox in their childhood.

In approximately 25% of cases, the foetus is infected by the virus as it passes through the placental barrier. Placental permeability increases as the pregnancy progresses.

  • Acyclovir therapy is prescribed to pregnant women infected with chickenpox. In 85% to 100% of cases, initiating acyclovir therapy will reduce or eliminate the symptoms of chickenpox. Acyclovir therapy is also started when a pregnant woman has been in contact with a possibly infectious person and is not certain of her own immunity.
  • Treatment should be initiated no later than 7 days from the first contact. Therapy is adjusted to a safe level during all stages of pregnancy.

Congenital varicella syndrome refers to permanent damage caused by a foetal chickenpox virus infection. Symptoms include scarring, rigidness of limbs, low birth weight, hydrocephaly, microcephaly, eye damage and mental retardation.

  • The foetal risk is greatest during the second trimester (weeks 13 to 24 of the pregnancy).
  • The risk of chickenpox virus infection increases after 24 weeks of pregnancy to 50%. However, damage to the foetus at this stage is very rare. Typically, the foetus will contract a mild form of chickenpox without severe or permanent damage.
  • Chickenpox infection increases the risk of premature birth. If the mother gets chickenpox close to delivery, the newborn baby may develop a severe form of chickenpox which could be fatal.


If there are no spots on the breasts, breastfeeding can be permitted as chickenpox virus is not passed into breast milk.


Herpes zoster is commonly known as shingles. The condition is caused by the varicella zoster virus which also causes chickenpox. Shingles is a local infection causing a belt-like rash. Although local, shingles may cause a chickenpox infection when a person who has not had chickenpox comes into direct contact with viruses shed from the rash.

  • If a mother develops shingles during pregnancy, the maternal antibodies will protect the foetus.
  • If a mother has shingles during delivery, it is recommended that the mother and child are isolated from other patients.

While breastfeeding, do not let the newborn baby come into contact with the vesicles.