Case of the Week - Waffu Bite

This has been the week of snake bites or Waffu bites as they are called in Mampruli, the local dialect.  At any given time we have two or three snake bites admitted to the hospital, but over the last week our wards have been full of snake bite victims.  The reason is that it is planting season here in Northern Ghana so everyone is out in the fields.  Although seen all year around, the snake bites peak in planting and harvest seasons. 

This patient was bitten on his foot

The snake that causes the most trouble here in Nalerigu is the Carpet Viper (Echis carinatus).   These are very aggressive snakes when disturbed.  The venom is a hemotoxin, meaning that the victims’ blood will not clot properly.  Depending on the amount of venom that is injected through the bite the symptoms can be as mild as just continuing to bleeding from the site of the bite, to internal spontaneous bleeding, which usually will lead to death if unable to reverse the clotting process.  Most typically we see swelling and blistering of the bitten limb.

When a patient comes in reporting that they were bitten by a snake the first thing we test is a Whole Blood Clotting Time (WBCT).  A small sample of blood is taken and left for 20 minutes.  After 20 minutes the blood is tipped on its side, if it is still liquid that means that no clotting has occurred and the patient was bitten by a carpet viper and has a hypo-fibrinogenemia coagulopathy.  The bites are treated with Anti-Snake Venom (ASV).  After given the ASV, the patient’s blood is tested 6 hours later to see if any clot will form.  If no clot forms they are given a second dose of ASV.  The process continues until the patient has three consecutive “clotted” WBCT and that point we will send the patient home.  Although it seems like an easy diagnosis and treatment, patients still do die from carpet viper bites.  I have seen at least three kids die over the course of my stay here.

My neighbor T holding a Cobra killed
outside a missionary's house

The second most common poisonous snake in Nalerigu is the spitting cobras (Naja Nigricollis).  Unlike the vipers, these snakes are generally provoked into attacking humans.  The bite of the cobra causes skin necrosis of the bite area that usually will spread to the fascia.  The cobra also can spit poison into the eyes of its victim causing a venom opththalma, which is characterized by corneal abrasions.  Treatment of the bites is giving ASV as well as local debridement of their necrotic wounds.  In the case of opthalmia, sterile eye irrigation and antibiotic eye drops are given to prevent secondary infection. 

The other creature the stings people here in Nalerigu is the scorpions.  The effect of a scorpion sting is mostly just severe pain at the sting site.  Very rarely are systemic symptoms seen.  Treatment is local injection of lidocaine or marcaine at the sting site for local pain control.

The people here in Northern Ghana are deathly afraid of snakes or “waffu."  Dr. Hewitt, a family practice doctor who has been stationed here over the past 20+ years, has been nicknamed Dr. Waffu by the locals, because he enjoyed carrying around a plastic snake to scare people in market or in his office.  Overall, my favorite part about seeing snake bite victims is when they bring the dead snake in to show you in clinic!  There is nothing like a patient sitting down on the stool next to your desk and pulling a snake out of a plastic bag.