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Many hotels spray for mosquitoes and sea breezes may keep them off of the beaches, so they may not be a problem while at the hotel. On outings, you should be prepared in case there are mosquitoes. Mosquitoes may be found year-round on the Pacific Coast of Mexico.

The mosquitoes we encountered near the Oaxacan coast were small and did not appear to have a bad bite. However the following day our bites became vivid red with tiny scabs on the top. They looked as though we had been scratching them (we hadn't). We wore these bites for over three weeks.

Many repellants are not effective on these tropical mosquitoes. One that is effective is called Autan classic and is manufactured by Bayer de Mexico. I understand that it is only available in Mexico. It comes in a white aerosol can with an orange and yellow front with a mosquito on it. Another that gives good results is Deep Woods Off, which is 95% N,N-dithyl-meta-toluamide. It is available in the U.S. and you can find it at Wal Mart with the camping equipment.

Also effective are the mosquito coils that you burn. We were being eaten alive at an open-air restaurant when our waiter brought one of these over and placed it underneath our table. We had no more problems with mosquitoes and enjoyed our meal. You can also buy these in Mexico. There is one called Raidolitos by Johnson that comes in a yellow box.

Another reader reports being happy with a product called Skeeter Free. "I was in Puerto Escondido last summer August. I am a mosquito magnet and decided to try something besides DEET. We were working on a Habitat for Humanity build from dawn until mid afternoon, so gave the little buggers lots of opportunity. I would re-spray about every 3-4 hours and was using the 2X version. It has a pleasant odor and slightly oily base so stays on even sweating. Based on Catnip! - Donna"

A reader reports buying an ointment in Mexico called "Andantol" in a yellow and black box to use on mosquito bites. This immediately reduced the swelling and kept the itch away. We have tried this and it works very well. Not for children under 6 years old. For a less toxic solution, there is Crocodile Herbal Bug Discouragent, an herbal bug repellant. The maker, Dancing Roots, has given away samples to tomzap.com readers in the past and positive results have been reported. See the 2006-2008 giveaway.

If you've already been bitten, After Bite is a product that has been recommended for relief.

Some visitors have asked if Malaria is a problem. Although rarely a problem for tourists, it does exist and has been a problem for some residents. A period of heavy rains increases the likelihood of an outbreak. This would most likely be after the rains come around August-September. A type of malaria they have in Oaxaca is called Vivax and is rather easy to cure. Symptoms are typically fever, vomiting, sweats and chills that persist for days or weeks. Outbreaks may be rather localized since the mosquito's range is only a mile or two. If you are concerned about malaria, see your doctor prior to leaving for preventative medication. Also, use your mosquito repellant when necessary.

Visitors to the coast of Oaxaca who wish to donate blood after their trip can expect a cool "thanks, but no thanks" due to the risk of malaria contamination.

Our readers contribute the following information on mosquito-borne diseases of the Oaxacan coast:

A Case of Dengue in Hidalgo

This will probably be pretty long, but I want to give the full account, because I never even new I was sick until it was too late.

My first symptoms were SPLITTING headaches. At least, that was the first symptom I recognized. I had probably been feverish before that, but put it off as maybe coming down with a cold. I don't suffer from migraines, but I would imagine that the Dengue headache was similar. I thought my brains were going to split my skull open right at the temples. It didn't matter how much ibuprofen and tylenol I took, nothing seemed to help much. Thought it might be due in part to dehydration, but drinking tons of water didn't help either.

IMPORTANT NOTE: DO NOT TAKE IBUPROFEN OR TYLENOL IF YOU THINK YOU MIGHT HAVE DENGUE!!! I learned that one a little late.

So, finally I took Tempra at the insistance of my mother-in-law and let her tie a cut potato to my temples, knowing full well it wouldn't do any good. BOY, was I wrong. The coolness of the potato instant relief, aided by the proper pain reliever. The key is that other pain relievers thin your blood and make internal bleeding more likely. Tempra does not thin your blood and so is the ONLY pain reliever recommended for Dengue in Mexico.

After a couple days of headache, I started having pain in my joints and bones. Now, I'm starting to put together the previous 'cold' symptoms, the crazy headaches, and the strangest pain I've ever felt in my life and look at the CDC sheet my major advisor made me bring with. Problem is, the CDC 'fact' sheet is TOTALLY INCOMPLETE and somewhat misleading. The bone pain is incredible, you can feel each and every bone in your body because it hurts like hell. I would have sworn my arms were about to break for no reason at all and I couldn't hold on to my 1 year old nephew's hand while he walked because I thought he was going to break my fingers. Slapped a mosquitoe on my leg and felt like I had been hit by a car. These are dramatic statements, but they are the truth.

After a couple days of joint and bone pain, I felt pretty decent for a couple of days. I noticed some generalized itchiness on my legs and arms, but couldn't really see any rash or cause of the discomfort. I put it off to heat rash or the bazillion mosquito bites I suffered every day, even though I was slathered in deet, even thought that might be the culprit. I, being a white girl, seemed to always be burnt, so when I thought my skin looked reddish asked the family if they thought the same. No, you're just burnt they said.

A couple days later I'm sure that I've got some kind of rash and I tell the family I think I have an allergy to something, or maybe I am sick. Well, with the fact that Hidalgo has no health center and the doctor in Mania isn't always around, going to the clinic got put off.

I was now at least 8 days into the illness and didn't really know I was even sick. I had done google searches on dengue and malaria and never got anything that was a red flag. None of the pages I found had a comprehensive list of possible symptoms or a 'timeline' of how the disease really goes. It was very confusing for me.

One day we were in town visiting an uncle and it became clear that I had a rash on my legs below my knees, on my arms from the elbow down and it was spreading, it was now showing up on my stomach and my thighs and upper arms (areas that weren't always burned and so it was easier to see). But, the itchiness was not there anymore. In retrospect, it seems dumb that I wouldn't put this all together, but everything I read seemed to say you get all these symptoms at once and you feel like shit and are really sick. I NEVER FELT SICK. I felt a little tired, but washing laundry by hand all day on a concrete sink can do that. Each symptom presented itself individually in my case, for a couple of days and then seemed to just go away. Since we were in Puerto this day that the rash took off, my father-in-law took us to a clinic next to a pharmacy. This is when I found out, I was really sick.

We walked in and before I could say, I have this strange rash the doctor told me I had hemorragic dengue and I should be at home in bed. I'm as skeptical as the next American about Mexican doctors, but we went through the 20 questions routine and he sent me to get blood drawn. At this point, the Dengue antibody test (I Think) showed negative - I found out later from another doctor that it won't show positive until at least 10 days after the headache/bone pain stage. But, my blood counts showed VERY low platelets and some other signs of dengue. The doctor told me to get another blood count in 24 hours, and drink plenty of fluids. THAT'S IT. He said maybe it wasn't dengue afterall because of the antibody test results. Come back tomorrow with your new blood test.

The following day I couldn't stand the rash and itching and I was really tired, so we went to the curandera that runs the pharmacy in Mania. She said it could be Dengue and that all I could do was take Tempra to control my fever and pain and sent me to the clinic. The doctor there said it was too early to jump to the conclusion that it was hemorragic dengue, and ordered more tests. We went immediately to the lab, got the bloodwork and went straight back to Manialtepec. This doctor was much more personable and explained what was going on to me much better. He said I should not be anywhere but in bed as my platelet count was dangerously low. I should be eating lots of green veggies drinking lots of gatorade and water and NOT DOING ANYTHING BUT RESTING. If my platelets got any lower, he said, I'd be sent to the hospital and if they couldn't get the count up I'd have to get a blood transfusion. He gave me a shot to stop the itchiness of the rash (not as fast-acting as I'd hoped) and told me to keep taking the Tempra every six hours and DO NOT GET OUT OF BED except to go to the bathroom.

LIKE HELL was I going to get a transfusion in Mexico! This is when I called my folks back home. She never told me, but Mom had gotten emergency time off work and was about to buy a ticket to come 'rescue' me and get me home for treatment.

Being this was Saturday night, I was ordered to the lab first thing Monday morning for another blood count. THANK GOD the numbers had started back up, but just barely. Several more days of bed rest and blood tests proved that I had just escaped a life flight back to Oregon.

SO, what I learned is this:

1. Sleep with a pavilion, PERIOD. The species (plural) of mosquito that carry dengue bite at night.
2. Be safe rather than sorry and use Tempra (paracetemol) for pain relief while in dengue territory
3. The rash was me bleeding out under my skin, thus the hemmoragic classification - hearing that got me scared.
4. There are four strains of dengue, each can present as classic and 'morph' into hemmoragic if not properly treated fast enough
5. Having one strain, classic or hemmoragic, does not make you immune to the other three strains
6. Even cases treated by doctors in clinics and hospitals are not neccessarily officially reported. This means more people in the community get sick because there is no special effort to get rid of the bugs
7. Classic dengue morphs when your blood is thinned, you are otherwise ill or rundown, you don't slow down when you first contract it (and stay slowed down), and probably for other reasons.
8. The only treatment, as it is a virus, is rest and pain relief. The only thing that they can do to try to save a hemmoragic patient is a transfusion.
9. Don't bother with the anti-body test, it won't show positive until you're on the mend or on the serious downhill slide. Get the bloodcount and make sure your platelets are at an acceptably high level.
10. Get a second or third opinion. Only the fresh from med school doctor in Manialtepec had clinical experience with any form of dengue - everybody else each had their own anicdotes but no two were alike. (I HIGHLY RECOMMEND USING THE CENTRO DE SALUD in your community. In Puerto Escondido it's down near the west end of the Adoquin where the road goes back to two-way traffic, in Chila it's by the soccer fields next to the Cobao, in Manialtepec its next to the municipio)
11. The CDC doesn't know shit. IF YOU HAVE ANY OF THE SYMPTOMS... GO TO THE DOCTOR. They can present simultaneously or singly, and singly they are easily brushed off as a myriad of non-serious things.
12. If your bones hurt, YOU HAVE DENGUE - go to the Centro de Salud

VC
July 10, 2007

I have lived for over a year in the Puerto Angel area and have acquired quite a bit of information about the mosquito situation. Some of this information comes from the Comisión Nacional para la Erradicación de Paludismo (CNEP), some comes from the Centers for Disease Control and some comes from the Physician's Desk Reference.

Mosquitos are a constant nuisance on the Oaxaca Coast. There are many types of mosquitos present; most are not the type that carry diseases. However, some types of mosquitos carry the diseases malaria and dengue fever. The risk of contracting these diseases is low although locally acquired cases of malaria do occur on the Oaxaca Coast. Although cases do occur year-round, most locally acquired cases of malaria occur during and after the rainy season (July to December).
In recent years the incidence of these diseases has become relatively low because of the efforts of Mexican public health authorities. These efforts include the spraying of the walls and ceilings of all homes, hotel rooms, restaurant and other businesses and buses with insecticides from the DDT and malathion families. After biting a person a mosquito will always rest on the nearest wall. The mosquito ingests a trace amount of the insecticide and dies before it can bite another person and spread disease.
This strategy has proved extremely effective and is employed in tropical areas throughout the world. The only adverse effect is that asthma sufferers may have a reaction to the insecticides. Many asthmatics have reported wheezing episodes and difficulty breathing while spending time in insecticide-treated rooms in the Mexican tropics. Asthma sufferers would do well to carry their inhalers and look for hotel rooms with plenty of fresh air.

The United States Centers for Disease Control states that the most effective method of preventing mosquito-borne diseases is to avoid being bitten by mosquitos.
Use a topical mosquito repellent containing DEET such as Bayer Autan. Bayer Autan is widely available in Mexican pharmacies. Avoid putting DEET on your face and wash your hands after applying it to your skin. Do not get DEET in your eyes.
Use mosquito coils. These coils burn like incense and contain chemicals that repel mosquitos. They are sold in stores in Mexico under the name Raid-O-Litos.
More natural remedies include taking garlic pills and Vitamin B-2 (Riboflavin). They give a scent to your blood and sweat that will repel mosquitos. Apply citronella oil to your exposed skin, although citronella should be re-applied every 30 minutes and will have to be brought from the United States or bought in a large Mexican city. Citronella candles are also available in the United States and it may be possible to find them in large Mexican cities.
Wear long pants and long sleeved cotton shirts if possible. Mosquito bed nets (mosquiteros in Spanish) are available in Mexican markets and stores. Nylon nets are more effective and more durable than cotton nets. Tucking your mosquito bed net under your mattress provides protection against scorpions and spiders as well.

The mosquitos that carry malaria are active primarily from dusk to dawn. Their numbers are greatest in the early evening hours. These mosquitos carry the P. vivax strain of malaria. P. vivax is a relatively benign infection.
Symptoms of an acute malaria attack include a high fever that comes on suddenly and then spikes upward and flu-like aches. An acute malaria attack can occur any time within a year after being bit by a malaria-carrying mosquito. There is no cure for malaria, but the P. vivax strain can be effectively suppressed by the medication Aralen (generic name: chloroquine phosphate). Aralen rapidly terminates acute malaria attacks although the P. vivax organism will continue to lie dormant in the body indefinitely.
The Physician's Desk Reference states that taking Aralen prophylactically (usually a dose of 500 mg on the same day each week) does not prevent malaria infection, but it may suppress the symptoms. If you are bitten by a P. vivax carrying mosquito while taking Aralen on a weekly basis, the P. vivax organism will still infect you and lie dormant in your body indefinitely. However you may not experience acute symptoms of malaria infection.
Aralen should be taken under medical supervision. It is usually dispensed in 500 mg tablets. The Physician's Desk Reference (PDR) warns that a dose of 750 mg to 1000 mg of Aralen (just two tablets) can prove fatal to a small child. If you think you are experiencing an acute malaria attack, go to the nearest hospital. Do not attempt to self-medicate.
When administered under medical supervision Aralen is regarded as a safe and effective medication. It has been around for many years.
Another malaria medication on the market, Lariam (generic name: mefloquine) is associated with severe side effects including psychotic episodes and long term psychiatric problems. Lariam was developed as a treatment for the so-called "chloroquine-resistant strains" of malaria. These are the strains of malaria that do not respond to Aralen (generic name: chloroquine). No cases of chloroquine-resistant malaria have been reported to be locally acquired on the Oaxaca coast. However recent epidemiological studies have demonstrated that chloroquine-resistant strains of malaria have been acquired farther south in Mexico and in Central America.
Travelers should be aware that there have been reports of travelers experiencing psychotic episodes and psychiatric problems while taking the anti-malarial drug Lariam (generic name: mefloquine).
The antibiotic doxycycline (from the tetracycline family of antibiotics) has been demonstrated to be effective in suppressing some strains of chloroquine-resistant malaria. Other anti-malarial medications are under development for the treatment of chloroquine-resistant strains of malaria.

The mosquitos that carry dengue fever are active primarily from dawn to dusk.
Dengue fever is a mosquito-borne disease that causes flu-like symptoms including high fever, painful aches, fatigue and malaise. Dengue fever is usually self-limiting and will resolve within a few weeks. A rare form of dengue known as dengue hemmoragic fever can be extremely serious. If you think you may be suffering from dengue fever, seek medical attention. There are presently no pharmaceutical treatments for dengue. Locally acquired cases of dengue fever continue to occur on the Oaxaca Coast. Dengue fever has only appeared in Mexico within the last few years. The outbreak of dengue fever followed a period of unusually hot and humid weather in Central America that may be linked to global warming. Dengue is a new disease and remains relatively mysterious.
To learn more about mosquito-borne diseases in Mexico and Central America visit the web page of the United States Centers for Disease Control in Atlanta, Georgia.

My wife and I live in San Francisco, CA and spend a good deal of time in Puerto Escondido. We were there last year at the end of August for a couple of weeks. After returning home to San Francisco I started to come down with something. At first I thought I had the flu, but low-and-behold it was confirmed as dengue fever. Excruciating!
I am a photographer and had been out in the woods of La Punta at the south end of Zicatela documenting the plants and birds of the area. I had found an interesting area deep in the woods that had an incredible rock outcropping and all types of mushrooms growing in a bog-like terrain. Sounds like a mosquito haven to me, and indeed it was. Great photos – but at a nasty cost.
I found a recent (3/30/07) article in Yahoo News that points to a surge in dengue in Mexico. 600% increase in Mexico since 2001. What's really scary is that about 10% of the cases are of the hemorrhagic kind – you bleed from your pores – not fun! Last year, Mexico documented 27,000 cases with 4,477 cases of hemorrhagic.

Andy Patrick
4/7/07

Repellent For Jejenes - According to an entomologist (bug expert) that I happened to meet in La Paz a few years ago DEET repellents are not really effective against an onslaught of vicious jejenes. He told me that DEET serves to mask the odor of carbon dioxide emissions from our skin, but the no-see-ums don't use CO₂ to find us like zancudos (mosquitos) do.

In addition to DEET I use a few drops of Pennyroyal oil on each limb, rubbing it in to thoroughly spread the oily extract evenly over the limb. I have had dramatic success with this even on the beach at San Blas at sundown (wearing shorts and t-shirt, no less!).

Pennyroyal Oil is available in health food stores. Most containers have an integral eyedropper which is handy. According to the health food gurus, women who are pregnant or in the process of becoming thereof should not use Pennyroyal Oil. The extract is supposedly safe for use on children, but a prudent parent should check with their doctor first.

Saludos de Tecatito!

David Eidell
deidell364@earthlink.net
December 2000

Try the Lime - When we were in Melaque in March/April both myself and my son seemed to attract some kind of no-see-ums that terrorized us. After spending a fortune on bug repellant (none of which seemed to work) we were told to try squeezing lime juice into your hand and rubbing it on, just like repellant. Viola! Worked great. We tried it at home, but unfortunately the Canadian no-see-ums don't seem to be deterred by lime juice.

Wendy Randall
wrandall@yknet.yk.ca
December 2000

Thanks for posting my write up on La Cueva so quickly. I was reading your section on mosquitoes, and thought I'd share this anti-itch method with you...

Mexican insects have absolutely no respect for lethal American-made chemicals manufactured for the express purpose of rendering them biteless. I never go outside without spraying liberal amounts of Cutter's or Deep Wood's Off insect repellent all over my body. I've even tried Autan. In spite of my preventative measures, if it bites, it bites me. So on top of whatever chemicals from the repellent have seeped into my body, I apply liberal amounts of cortisone cream to ease the itching. Cortisone, I'm told, thins the skin, and at my age the skin thins anyway. La vida es dura en Mexico!

One day I watched a friend of mine hold the lit end of a cigarette close to his skin. Knowing him to be too old and sensible to be into self-mutilation, I asked him what he was doing. "It's an old Mexican remedy," he said. Apparently if you hold a cigarette, or I suppose anything very hot such as a newly extinguished match head, close enough to the insect bite to feel the heat but not actually burn yourself, it stops the itch and makes the swelling recede.

Admittedly, this method is a bit more challenging than applying a potion, as it does require a somewhat steady hand. But I've tried it, and it really WORKS! The itching stops, the swelling goes down, and evidence of the bite disappears faster than with cortisone preparations. If the bite starts itching again, repeat the procedure.

I hope no one who's stopped smoking uses this as a rationale to start again. But it is a viable alternative to chemicals.

Jane Gorby
La Manzanilla
jgorby@ciber.net.mx
October 2000

see a 1998 Malaria Advisory that affected the Oaxacan coast and learn about email updates.

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The Pacific Coast of Mexico www.tomzap.com Tom Penick:  tom@tomzap.com