In any other year, just about the scariest public health warning for the people of the Sonoran Desert is the annual talk about how to avoid those really painful scorpion stings. 

This year, however, folks who share the border between Yuma County, AZ and San Luis Rio Colorado in Sonara, Mexico have something even more terrifying to worry about. Two dozen of their neighbors are suffering from muscle weakness to full blown paralysis.

Two dozen residents of this sun-drenched land are victims of a rare disease called Guillain-Barré syndrome (GBS), which involves the body’s immune system attacking the peripheral nervous system.

With less than 200,000 in the Yuma area on the U.S. side of the border, and about 140,000 in all on Sonara on the Mexican side, public health officials might expect three or four GBS cases a year.   

Quick growth of a cluster that has reached 24 confirmed cases — the latest onset occurring during the first week of July — caused alarms to go off with public health officials on both sides of the border.  One Mexican man, who had a pre-existing condition, died after GBS struck.

Federal, state and local health departments in the U.S. and Mexico have been mobilized for most of the summer, trying to identify the cause of the GBS uptick.  Seven victims reside in Yuma and 17 in Sonora, according to Omar Contreras at the Arizona Department of Health Services.

State officials say hospitals in Phoenix, Tucson and Flagstaff have been pressed into providing the sophisticated treatment sometimes required for GBS-induced paralysis.

Contreras says the local-state-federal teams have interviewed more than 100 people involved with the cluster of GBS cases and the data are still being analyzed.  Will Humble, director of the Arizona Department of Health Services, says there may have been more diarrheal illnesses due to reduced water quality.

The more common waterborne and foodborne pathogen called Campylobacter was identified as a precursor for some, but apparently not all, the GBS cases, according to Contreras.   Only one in 1,000 cases of Campylobacter infection usually goes on to develop GBS.

While waiting for the all the data they created to be analyzed,  the public health officials have persuaded those who run the water systems to increase chlorine levels.

While those who come down with GBS generally recover, it is a very scary experience.  Contreras says the symptoms usually begin with finger and toes getting prickling sensations like pens and needles.  It can move quickly to a point where the person cannot walk or make typical moves like speaking, chewing or swallowing.

Victims are advised to seek medical attention as soon as the  tingling in feet, toes, or hands is felt because it can so quickly reach a point in which loss of bladder control, rapid heart rate, blood pressure, and breathing problems develop.

GBS outbreaks like the one being experienced on the Yuma/Sonora border are rare and not very well understood. While GBS typically develops after an infection, it is not contagious.

Contreras says Arizona officials are hopeful that they seen their last case for this cluster.  He says physicians in the area are definitely on the lookout for GBS symptoms.

While GBS is not passed from person to person, state officials have still been urging residents to avoid infections that might be precursors to GBS by good hand-washing habits and safe food preparation.  They are reminding people to wash their hands thoroughly after using bathrooms, before and during cooking, and before eating.

About 85,000 “snowbirds” make the Yuma area their winter home.   

As for those scorpions, more than 10,000 Arizonians annually get stings with about 200 children ending up in hospital intensive care.