What is the Marburg virus?

The Marburg Virus is a serious and potentially life-threatening viral infection that can affect several organs such as the spleen, liver, and lymph nodes. The virus is named after the city Marburg, Germany, where the first outbreak occurred in 1967 after a group of African Green Monkeys were imported by a laboratory.¹ The virus is classified as a type of viral haemorrhagic fever (VHF).

This means that it targets the blood vessels, which can lead to internal bleeding but also bleeding from eyes, ears, nose, and mouth. The better-known Ebola Virus also belongs to this group.² The few outbreaks that have been reported in recent times, have occurred in various countries such as Angola, Democratic Republic of Congo (DCR), Uganda, and Kenya. 

The virus commonly spreads from animal to human, with fruit bats being the most well-known carrier of the virus. However, it has been known to spread from eating bush meat. The virus can also be spread from human to human via direct contact with the bodily fluids of infected individuals, such as urine, saliva or blood, or indirectly via contaminated surfaces and materials. There is even an extremely rare case of the virus being contracted via sexual contact.² 

Pregnant patients are particularly at risk, as they are more likely to experience the more severe symptoms. Unfortunately, there is a near 100% rate of pregnancy loss, even in cases where the mother survives. For this reason, it is important to know what makes pregnant patients more vulnerable and what can be done to protect them.

Symptoms

Symptoms are similar in both pregnant and non-pregnant patients. 

You can also develop the following symptoms:

• Painful swallowing
• Chills
• Muscle aches and pains
• Headaches 
• Patches of small red, non-itchy rashes on the skin² 

According to the World Health Organisation (WHO), the fatality rate is 24% to 88% with death occurring around Day 8 – 9 after the start of the infection, usually due to multi-system organ failure, shock from extreme blood loss or extreme dehydration from excessive vomiting and diarrhoea. Even though Marburg Virus is infamous for causing mass bleeding, this symptom only occurs in 18% of reported cases.³

Risk to pregnant patients

There are only a handful of cases of Marburg infection in pregnant patients. From these cases, it was estimated that pregnant women had a 74% – 100% fatality rate, much higher than non-pregnant patients. Symptoms also tend to be more severe in pregnant patients.³

But why are pregnant patients more vulnerable than other groups? One culprit could be the hormone progesterone. Progesterone is a hormone produced in people assigned female at birth (AFAB) that plays a significant role in maintaining the early stages of pregnancy.

One of the many functions is suppressing certain immune responses. This is beneficial to the developing foetus as it stops the mother’s body from seeing it as a foreign threat and terminating it. However, this comes at a cost to the mother, as it means that they are more at risk of an infection developing.⁴

Can the virus harm the foetus? Studies have found high viral load in amniotic fluid and placental tissue of pregnant patients. This means that there is evidence that the virus can cross the placenta and infect the foetus as well.³ The survival rate for the developing foetus is extremely low, with a near 100% chance of a miscarriage or stillbirth occurring.

Diagnosis

A PCR test on the patient’s blood sample would be conducted to confirm that Marburg Virus is the disease-causing pathogen. The PCR test will detect genetic material from the virus to confirm its presence.

It would be very difficult to diagnose the infection based on symptoms alone, especially in pregnant patients. There are many reasons why a pregnant patient might be experiencing unexpected bleeding, such as miscarriage or excessive vomiting, like morning sickness.

This would lead to misdiagnosis and insufficient treatment.³ Clinicians may also ask about your travel history to see if you have travelled to any places that had any recent outbreaks or places that could increase your risk of exposure to animal vectors such as fruit bats. 

Treatment options for pregnant patients

There is no direct cure for the Marburg Virus infection. The only current treatment plan is to provide supportive care to manage the symptoms with the hope of recovery. Pregnant patients would require much stricter observations.

Fluid replacement

Dehydration is one of the main causes of death from a Marburg virus infection as a result of extreme diarrhoea and vomiting. Dehydration leads to a loss of important electrolytes, such as potassium and sodium. Electrolytes are important for regulating heart function.

If electrolytes are not balanced properly, arrhythmia — a potentially life-threatening heart condition — can occur. To prevent this, anti-emetic and antidiarrhoeal treatments will need to be given to the patient to help manage vomiting and diarrhoea symptoms. Pregnant patients will also need at least 5 – 10 litres worth of IV fluid or oral solution daily to reverse the dehydration.

If blood loss from haemorrhaging is also a concern, blood transfusion therapy will need to be considered.³ Vitals such as oxygen levels and blood pressure will also need to be stabilised. Due to the location of some outbreaks, patients may also have some coinfections, such as malaria and roundworm.⁵ 

Foetal monitoring

The biggest challenge that will need to be taken into consideration is the balance between maternal care and foetal care. Since there is such a poor prognosis for foetal survival, priority will most likely go to ensuring the survival of the mother. Labour induction may be considered, but the risk of further blood loss might negatively affect the mother’s chance of survival.

Caesarean section is not recommended as it is almost certain the foetus will contract the virus via this method.³ While physical recovery is very important, the need for mental and emotional care should not be underestimated. Pregnancy loss can be an extremely distressing and traumatic experience for the patient, and so aid in this area should be taken into consideration. 

Antiviral treatment

Currently, there is a lack of active antiviral treatments to combat Marburg infection. However, this may change in the future. There is a growing number of potential treatments in the testing phase that could be useful:

• Galidesivir — broad-spectrum antiviral drug used to stop viruses from multiplying 
• Favipiravir — already used to treat Ebola, which has many similarities to the Marburg Virus⁵

Both have shown positive results in animal studies, but only data from human trials will show if they are truly effective against Marburg infection. There is also a great need for effective and accessible prophylaxis, especially for pregnant patients who live in areas prone to outbreaks. 

Prevention for pregnant women

The old saying goes: “prevention is better than cure”. Given the lack of treatment options, prevention is vital for the safety of pregnant mothers. The vast majority of infections happen as a result of coming into contact with contaminated objects or animals/people with the infection.

This means healthcare workers are most at risk of contracting the infection. Healthcare workers are strongly advised to wear Personal Protective Equipment (PPE) especially if they come into contact with bodily fluids regularly as part of their duties. If it has been confirmed that someone that you know or come into close contact with on a regular basis has the infection, it is vital that they isolate themselves and seek medical attention immediately. Any items, bedsheets, towels etc. used by the infected individual should be disposed of as soon as possible.

Making use of good hygiene practices, such as handwashing and the use of alcohol gels can help minimise the spread of the virus. You must avoid areas that have a high population of animals that are potential carriers and outbreak areas to reduce the risk of exposure, such as caves with a high population of fruit bats.

Studies have shown that anyone who makes a full recovery from a Marburg infection can gain long-term immunity and will not be at risk of being contagious. However, viral particles have been found in semen and breast milk samples of recovered patients. As such, infected individuals should not breastfeed or engage in sexual activities for a minimum of 15 days after recovery.³

Summary

The Marburg Virus is a life-threatening infection that poses a great risk to pregnant patients and the developing foetus. The virus can be spread via contact with infected individuals, infected animals and contaminated materials and surfaces. Pregnant patients are more vulnerable, as pregnancy hormones like progesterone can dampen the immune system. While there is a chance for the mother to make a recovery, there is a near 100% chance of pregnancy loss or stillbirth occurring. 

Currently, there are no vaccines or effective treatments capable of fighting the infection, thus prevention is vital. Good hygiene practices, wearing PPE, and isolating yourself from animals and people with the infection are effective means of protection. If you are pregnant, have travelled to an area with a reported recent outbreak and have experienced any of the discussed symptoms, please seek immediate medical attention.