How To Avoid Dengue Zika During Pregnancy

Dengue Zika Dengue Zika

CDC has updated guidelines that contain a recommendation for routine care for babies whose mothers traveled to or resided in areas with Zika virus outbreak during pregnancy. Dengue Zika manifests itself by fever, rash, arthralgia, or conjunctivitis. Evidence shows that Zika virus disease in children is usually mild. Healthcare providers should report suspected cases to their local or state health departments so that action can be taken to reduce the risk of local Zika virus transmission.

Zika and Pregnancy

Zika virus is transmitted to humans through the bite of Aedes species mosquitoes, especially Aedes aegypti and Aedes albopictus. Zika virus was first found in Brazil in the spring of 2015 and had spread to tropics and subtropics throughout the world. In October 2015, a significant increase in the number of babies born with microcephaly was reported. Zika virus can be transmitted from an infected mother to her infant, through sexual transmission and laboratory exposures. Besides, blood transfusion and organ transplantation also pose theoretical risks of transmission. There is no evidence of transmission through breastfeeding even though Zika virus RNA has been found in breast milk.

The incubation period of Zika virus is likely from three days to two weeks. Mother-to-infant transmission during the perinatal period has led to findings in the newborn ranging from no symptoms to serious illness (including fever, hemorrhage, and thrombocytopenia), with fever onset during the first week. The clinical features that should be observed in infants who contract Zika virus during the perinatal period are still unknown. Deaths from Zika virus infection seem to be rare in people of all ages. Guillain-Barré syndrome is believed to follow Zika virus infection even though a causal connection has not been established. Guillain-Barré syndrome incidence seems to develop with increasing age.

The results of prenatal ultrasounds and maternal testing should be considered. A thorough newborn physical examination, with measurement of head circumference, length, and weight, should also be conducted. It is important to evaluate infants with microcephaly or intracranial calcifications or babies whose mothers have positive test results for Zika virus infection. Healthcare providers should perform clinical judgment in newborns with abnormalities such as microcephaly or intracranial calcifications. They also should test the mother before testing the baby.

Evaluation of children for acute Zika virus infection should include testing of serum and cerebrospinal fluid (CSF) specimens by using RT-PCR. If Zika virus RNA is not found and symptoms have been present for more than four days, serum may be tested for immunoglobulin M (IgM) and neutralizing antibodies. In any clinical specimen, laboratory evidence of Zika virus infection would include Zika virus in culture, Zika virus RNA, or a clinical specimen positive for IgM. More information on laboratory testing is available online.

Illness associated with Zika virus is often mild, and treatment involves supportive care. Nonsteroidal anti-inflammatory drugs (NSAIDs) should be avoided due to the potential for hemorrhagic complications. Aspirin should not be used in children and teenagers with acute viral illnesses due to its association with Reye’s syndrome. The decision to perform additional laboratory tests, diagnostic studies, and disease consultation should be based on clinical judgment and findings from a full history and physical examination.

Chikungunya Symptoms Dengue Zika

Zika virus RNA has been detected in breast milk but attempts to culture the virus have not been successful yet. No cases of Zika virus infection through breastfeeding have been reported. CDC recommends mothers with Zika virus infection who live in or travel to areas with ongoing Zika virus outbreak to breastfeed their babies. The benefits of breast milk are more valuable than the theoretical risks of Zika virus transmission through breastfeeding.

Prevention of mosquito bites is the best means of preventing Zika virus infection in people of all ages residing in or traveling to areas with ongoing Zika virus transmission. Wear long-sleeved shirts, long pants, or any clothing that can cover as much exposed skin as possible. Purchase permethrin-treated clothing and gear. Use air conditioning or window and door screens when indoors. Apply insect repellents; most EPA–registered products can be used on children, pregnant women, and lactating women. Oil of lemon eucalyptus is not good for children under three years of age. Cover carriers, strollers, or cribs by mosquito netting to protect infants from mosquito bites.

Evidence indicates that Zika virus infection during pregnancy leads to microcephaly. Studies are underway to confirm the association between Zika virus infection and microcephaly, as well as the role of other factors (e.g., previous infections, nutrition, and environment). Other problems appear among fetuses and infants infected with Zika virus before birth, such as poorly developed brain structures, impaired growth, and defects of the eye. Researchers are collecting data to understand how Zika virus affects mothers and their children. Pregnant women in any trimester should not travel to an area where Zika virus is prevalent. If the travel is compulsory, she should consult with her healthcare provider or obstetrician. She needs to follow strict steps to avoid mosquito bites. If a pregnant woman has a sexual partner who lives in or has returned from an area with Zika, the couple needs to either use condoms or abstain from sex for the duration of her pregnancy.

Chikungunya Fever Amniocentesis

Consideration of amniocentesis should depend on the patient’s clinical circumstance, the evaluation of potential Zika virus infection and other congenital infections. Healthcare providers should thoroughly explain the risks and benefits of amniocentesis to their patients. However, amniocentesis is not advisable until after 15 weeks of gestation. The exact timing of amniocentesis must be individualized based on the patient’s clinical circumstances. Referral to a maternal-fetal specialist may be necessary.

In the special context of Zika virus disease, it is crucial for women and their partners to plan pregnancies. Obstetricians should discuss reproductive life plans, especially pregnancy intentions and timing with women of childbearing age. This discussion should include signs and symptoms of Zika, the possible adverse outcomes of Zika infection during pregnancy, and an assessment of the risk of dengue Zika exposure. Do not miss factors that might influence the timing of pregnancy, such as age, fertility, medical history, reproductive history, and personal values and preferences.

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The Best 5 Tests In The World To Detect Dengue Syndrome

Dengue Fever Virus Dengue Syndrome

Dengue can be diagnosed by serological tests, by molecular methods, or by isolation of the virus. Diagnosis of acute or recent dengue syndrome can be made by testing serum samples during the first five days of symptoms and early convalescent phase. Methods such as one-step nested RT–PCR, or real-time RT–PCR are now widely used to identify dengue viral genes in acute-phase serum samples.

Laboratory Guidance and Diagnostic Testing

Chikungunya Symptoms Flaviviruses

IgM antibodies for dengue virus may remain elevated for two to three months after the illness. The elevated IgM found in a sample could be the consequence of an infection that occurred two to three months ago. Besides, there is a cross reactivity with other flaviviruses such as Japanese encephalitis virus (JEV), St. Louis encephalitis virus (SLE), West Nile virus (WNV), and yellow fever virus (YFV). The doctor should review the patient’s medical history, travel history, and vaccination record to determine the likelihood that the ongoing acute febrile illness is the result of an infection with dengue virus. Quite often, both an acute and convalescent-phase specimens are necessary to make a diagnosis of dengue virus infection. This is especially true for those who suffer a five-day acute specimen since the virus and IgM antibodies can be at undetectable levels. If a patient with suspected dengue infection develops a negative late acute phase specimen (e.g., by MAC-ELISA and RT–PCR), and they do not suffer a convalescent specimen, they are defined as a laboratory-indeterminate case.

Testing Algorithms for Dengue

1. PCR
Dengue virus can be detected in the blood (serum) of patients for the first five days of symptoms. At this juncture, several PCR tests are used to detect the viral genome in serum. Moreover, additional characterization requires virus that are isolated and sequenced. Real-time RT–PCR assays have also been developed and employed, but none of these tests are commercially available. Since antibodies are identified later, RT–PCR has been a primary tool to detect the virus in the early course of illness. Current tests are 80-90% sensitive and 95% specific. A positive PCR result is a proof of current infection; it also confirms the infecting serotype. A negative result, however, is considered indeterminate.

MAC-ELISA (IgM antibody capture ELISA) format is often employed in diagnostic laboratories and commercially available diagnostic kits. The assay depends on capturing human IgM antibodies using anti-human-IgM antibody followed by the supplement of dengue virus specific antigen. One of the limits of this testing is the cross reactivity among other ongoing flaviviruses. This limit must be considered in regions where various flaviviruses co-circulate. IgM detection is not helpful for dengue serotype determination because of cross-reactivity of the antibody.

The IgG ELISA is used to detect a past dengue infection. This assay avails of the same viral antigens as the MAC-ELISA and correlates with the hemagglutination assay (HI). IgG ELISA lacks specificity inside the flavivirus serocomplex groups. Primary versus secondary infection can be determined by a simple algorithm. Samples with a positive IgG in the convalescent phase and a negative IgG in the acute phase of the infection are primary infections. A secondary dengue infection includes samples with a positive IgG in the acute phase and a rise in IgG titer in the convalescent phase (with at least a seven-day interval between the two samples).

The NS1 ELISA based antigen assay is available for dengue virus; many investigators have assessed this assay for sensitivity and specificity. The non-structural protein 1 (NS1) has proved to be a useful tool for the diagnosis of acute dengue infections. It may also be useful for different diagnostics between flaviviruses due to its specificity.

PRNT (Plaque Reduction and Neutralization Test) and the microneutralization PRNT could be used when a serological specific diagnostic is needed since this assay is the most specific tool for the detection of dengue antibodies. The PRNT test identifies the infecting serotype in convalescent sera. It measures the titer of the neutralizing antibodies in the blood of the infected individual and evaluates the level of protective antibodies this person has towards the infecting virus. It is a biological assay based on the fundamental of the interaction of virus and antibody leading to inactivation of virus that is no longer able to infect and duplicate in cell culture.

Immunological Response to Dengue Infection

Chikungunya Fever Immune Response

The immune response varies depending on if the individual has a primary versus a secondary dengue infection. In a word, diagnosis of dengue depends on the phase of the infection. A primary dengue infection manifests itself by a slow, low titer antibody response. The first immunoglobulin isotype to appear is IgM antibody. Anti-dengue IgG is detectable at the end of the first week of illness and slowly rises. During a secondary infection, in contrast, antibody titers increase extremely rapidly and antibody reacts with many flaviviruses. High levels of IgG are detectable in the acute phase, and they multiply dramatically over the two following weeks. The kinetics of the IgM response is variable. IgM levels are considerably lower in secondary dengue infections and hence some anti-dengue IgM false-negative reactions are found during secondary infections. 80% of all cases have detectable IgM antibody within five days of illness, and 93-99% of cases contain detectable IgM within six to ten days of illness, which may remain detectable for the next 90 days.

MAC-ELISA is an important tool for dengue syndrome diagnosis. It has a sensitivity and accuracy of approximately 90% and 98%, but only when conducted five or more days after onset of fever (in convalescent phase). Different formats such as AuBioDOT IgM capture and dipsticks, capture ELISA, capture ultramicro-ELISA, and dot-ELISA have been developed. Serums, saliva, and blood on filter paper are useful for IgM detection when samples are collected in convalescent phase of illness. A plenty of different commercial kits is available with various sensitivity and specificity. Dengue diagnosis becomes more challenging since dengue IgM antibodies also cross-react with other flaviviruses such as JEV, SLE, WNV, and YFV.

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