DEAR DR. ROACH: In January 2014, I was bitten by a mosquito in the Caribbean and came down with the Chikungunya virus, which I still have. I took naproxen for about three months for the Chikungunya from April to July 2014. In August, I started having chronic diarrhea, which continues to this day. I have approximately three watery diarrhea attacks per day and must go to the bathroom ASAP three to four times over the period of an hour or two, with each attack.

Recently, I went to a gastroenterologist, who prescribed prednisone, saying that he felt the Chikungunya had caused my immune system to go into overdrive and that this was what was causing the diarrhea. The prednisone gave no relief. I have had a colonoscopy, with nothing but four polyps showing up there, and I was prescribed and have taken Flagyl, with no relief there either. I also had a FIT test, which came back negative, showing no blood in my stool.

I would appreciate any advice that you could give me concerning this most disabling situation. — B.W.J.

ANSWER: Chikungunya, despite its funny-sounding name, is a serious and increasingly common disease seen in North America from visitors to South America, the Caribbean, central and southern Africa, and south and southeast Asia. There also have been cases acquired in Florida. It is likely that there will be more cases, so it’s important to know more about it.

Symptoms begin within a week of being bitten by an infected mosquito, and the most common symptoms are joint pain and fever. Although there can rarely be serious complications, most people start feeling better within one to three weeks. The joint pain can last for months, or even years in some people. It can look like dengue fever, and blood tests may be necessary to confirm the diagnosis. There is no specific treatment and no vaccine.

I could not find any information on Chikungunya virus causing diarrhea symptoms lasting past the initial phase, and I am concerned that you may have picked up another cause for diarrhea on your trip. A colonoscopy was a good idea, but I think it’s time you got a second opinion, and I would find a specialist in infectious disease, someone who has experience in diseases of returning travelers.

That being said, it would be unusual to have an infectious cause of diarrhea show up seven months after the travel. It’s possible you have a totally different cause for chronic diarrhea. Your symptoms have some resemblance to irritable bowel syndrome; however, I think it would be a mistake to make that diagnosis without a thorough workup for chronic causes of diarrhea.

DEAR DR. ROACH: I recently recovered from sigmoid colectomy surgery, and I would hate to repeat this, given that I am 75 years old. What are the possibilities of recurrence of diverticulitis for which the surgery was performed? It’s nothing I’d care to undergo again if it can be avoided! — C.K.

ANSWER: Surgery for diverticulitis is generally reserved for people with multiple recurrences. The sigmoid colon tends to be the portion of the colon with the most diverticula (small pouches in the wall of the colon that may get inflamed or bleed). Surgery usually is curative, with only 15 percent of people developing new diverticula and only 2 to 11 percent needing further surgery.

It’s not proven, but most authorities believe that reducing pressure in the colon with a high-fiber diet reduces risk of developing diverticula, either recurrent after surgery or in the first place.

Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to ToYourGoodHealth@med.cornell.edu or request an order form of available health newsletters at 628 Virginia Dr., Orlando, FL 32803. Health newsletters may be ordered from www.rbmamall.com.