Peru declared a 90-day national health emergency on Saturday due to an "unusual increase" of cases of Guillain-Barre syndrome.

The country has so far registered 165 cases and four deaths due to the disease.

The decree, published in the official gazette El Peruano, details an action plan which has been drawn up with a budget of 12.12 million soles (3.3 million U.S. dollars) with an aim to improve patient care in health facilities, reinforce case control and prepare informative material for the population and health personnel, Xinhua news agency reported.

Among the measures were the acquisition of intravenous immunoglobulin and human albumin, as well as specialized diagnosis of the biological agents associated with the syndrome and assisted air transport for patients in emergency or critical condition, reported the Chinese news agency.

What is Guillain-Barre syndrome?

As per Mayo Clinic website, Guillain-Barre (gee-YAH-buh-RAY) syndrome is a rare disorder in which your body's immune system attacks your nerves. Weakness and tingling in your hands and feet are usually the first symptoms.

These sensations can quickly spread, eventually paralyzing your whole body. In its most severe form Guillain-Barre syndrome is a medical emergency. Most people with the condition must be hospitalized to receive treatment, read the website.

The exact cause of Guillain-Barre syndrome is unknown. But two-thirds of patients report symptoms of an infection in the six weeks preceding. These include a COVID-19, respiratory or a gastrointestinal infection or Zika virus.

Is there any cure?

There's no known cure for Guillain-Barre syndrome, but several treatments can ease symptoms and reduce the duration of the illness.

Although most people recover completely from Guillain-Barre syndrome, some severe cases can be fatal, reports Mayo Clinic website.

While recovery may take up to several years, most people are able to walk again six months after symptoms first started.