Chicken pox in pregnancy : an obstetric concern.

Chicken pox is a common viral infection presenting with fever and discrete vesicular lesions. This infection can be widely detected in developing countries, especially for those tropical countries. The pregnant can get chicken pox, and this becomes an important obstetrical concern. In this specific paper, the author hereby details and discusses on chicken pox in pregnancy. Clinical presentation, diagnosis, treatment, and prevention are briefly summarized. In addition, the effects of chicken pox on pregnancy as well as the vertical transmission are also documented.

Introduction

Chicken pox is a viral infection. This infection has its clinical presentations as high fever with generalized vesicular lesions.[12] This is a highly contagious disease. This disease is considered as an important infectious disease in surveillance program. In the past, the disease usually occurred in the pediatric population.[12] However, due to the improved sanitation in this day, the epidemiology of disease changes and the disease hits the higher aged group.[3]

In tropical country, chicken pox is common.[4] However, it is also detectable in the developed nontropical countries. The problem on infection in pediatric cases is not as much as that of non-pediatric case. In adult infection, the patients might suffer from many complications of chicken pox, especially for lung complications[35] Similar to other population, the chicken pox among the pregnant subjects can be seen, and this becomes the concern in obstetrics.

Clinical Presentation of Chicken Pox in Pregnancy

Similar to general population, there is no difference in clinical presentation of chicken pox in pregnancy.[6-13] The pregnant subjects who get chicken pox will develop the high fever and can last for 7 days due to the nature of viral infection. Chicken pox is classified as a respiratory infection.[12] This viral infection is highly contagious. The skin lesions usually help clinical diagnosis of the disease. Usually, the pruritic skin lesions start after 1-2 days of fever.[6] The vesicular skin lesion is the hallmark of the disease. The vesicles can be easily ruptured and serous fluid can be detectable. The contact with skin fluid can be another mode of disease transmission. Similar to general adult population, the pregnant can develop chicken pox pneumonia. Focusing on chicken pox pneumonia in pregnancy, there is no difference in clinical outcome or presentation.[14]

Diagnosis of Chicken Pox in Pregnancy

As earlier mentioned, the diagnosis of chicken pox, either in pregnant or non-pregnant subjects can be easily performed on the basis of clinical history and clinical classical signs-symptoms.[6-13] There is no need for laboratory diagnostic tool.[15] However, there are also some available laboratory diagnostic tools including virus/viral antigen detection, virus isolation, and identification or serological diagnosis. These tools might be useful for atypical cases.[16] The cost utility of those laboratory diagnostic tools is still not approved.

Treatment of Chicken Pox in Pregnancy

In pediatric population, chicken pox can be self-limited without any specific antiviral drug treatment.[12] There is no need for this scenario. However, the use of specific antiviral drug, acyclovir, is recommended in non-pediatric group since this group gets higher risk of complication.[17-19] The dosage form of acyclovir is 800 mg per oral for five times per day for continuous 7 days.[17] For the pregnant subject, the treatment by acyclovir is recommended for special precautions.[20] However, there are many reports confirming the effectiveness and safety of acyclovir for treatment of chicken pox among the pregnant. Nevertheless, there is still a need for systematic assessment on the risk-benefit of using acyclovir in this scenario.[20] However, use of acyclovir in pregnancy seems to be acceptable similar to general population. Frenkel et al reported that the administration of acyclovir, 400 mg every 8 h, appears appropriate for use in an efficacy and safety study regarding suppression of herpes simplex virus recurrences during the last weeks of pregnancy.[21] Another problem to be concerned is the management of the presumed susceptible chicken pox exposed gravid. Rouse et al gave an opinion on this issue that from a cost-effectiveness/cost-benefit standpoint, management based on immune testing is preferable to universal varicella-zoster immune globulin administration when caring for the varicella-exposed gravida with a negative or indeterminate infection history.[22]

Prevention of Chicken Pox in Pregnancy

The routine infection control process can be useful in prevention of chicken pox.[12] Specific vaccine for chicken pox is available. However, the cost-effectiveness of this new vaccine is assessed in many countries. In the endemic country, there is still evidence that the chicken pox vaccine is not cost-effective for general population and should be considered for the risk groups such as medical personnel.[2324] For the pregnant subject, there is no routine recommendation for vaccination for chicken pox in case with or without clear previous history of infection. The safety in case of vaccine is used is also a big concern. Wilson et al noted data collected in the pregnancy registry to date do not support a relationship between the occurrence of congenital varicella syndrome or other birth defects and varicella vaccine exposure during pregnancy.[25]

Effect of Chicken Pox on Pregnancy

The effect of chicken pox on pregnancy is not well defined. It is still a query whether chicken pox can lead to abortion or preterm labor. Focusing on the effect on fetus, there is no report on congenital anomaly due to maternal chicken pox. However, the infection, which can be confirmed by amniotic fluid or fetal blood test for viral DNA, and fetal histopathological change, as miliary calcified necroses in fetal organs, are confirmed.[26] Prenatal diagnosis on the problem can be presently done. Nevertheless, it is confirmed that chicken pox can have vertical transmission mode.[2728] Sauerbrei noted that intrauterine death or severe diseases (congenital or fetal varicella syndrome) may ensue depending on the time of maternal infection.[9]

Vertical Transmission of Chicken Pox

The vertical transmission of chicken pox is confirmed. Auriti et al mentioned for the need for expert medical counseling for women who contacted chickenpox at any time during pregnancy.[28] Auriti et al also raised for the importance of immunizing susceptible women of childbearing age before they became pregnant.[28] There are some sporadic reports on this mode of transmission.[25] Usually, the mother gets the infection at term and the infant present with specific vesicular skin lesion confirming the appearance of congenital chicken pox.[2627] Acyclovir treatment of the affected neonate with congenital chicken pox is also recommended.[2627] Indeed, the serious congenital infection might be preventable with passive antibody prophylaxis and antiviral therapy.[29]