Proceedings of the Seventy-Ninth Annual Meeting of the New Jersey Mosquito Control Association, Inc. 1992, pp 133-136.
(Please use this citation when referring to this work)
HOWARD EMERSON, Camden County Mosquito Extermination Commission, County Complex, Egg Harbor Road, Lindenwold, NJ 08021
The preceding presentations have detailed the investigation of this case and the history of malaria in New Jersey. My report begins with my reaction to learning of this case of malaria in my County. I thought of how one reports on a case of a well known disease that was believed to have been eliminated from the area for the last forty years. People in this room have been known to debate if our work should be described as disease control or as nuisance control. Some feel that all of the famous and important diseases have been conquered. Malaria is a good example of this. Doctors can eliminate Plasmodium vivax from the blood of a victim and thus eliminate the reservoir of the disease. Control of the vector of the disease, the mosquito, may never be addressed . On the other hand, most communicable diseases declined in case rate long before doctors could cure them. Previous generations of mosquito control workers undoubtedly prevented millions of cases of a number of diseases over the years. It seems also that a number of other diseases were prevented by clean drinking water and the proper sanitary disposal of sewerage. Thus, mosquito control workers and plumbers have, through the years, prevented many diseases and deserve considerable credit. In the present day the infrastructure related to plumbing and clean water receives considerable more attention and funding than mosquito control.
Explaining this case form the proper prospective for the public was important. Certainly the public needed to know so that any action they could take to protect themselves from mosquitoes would prevent additional cases.
At the time of this case, the County was in a budget crisis. Layoff procedures were in place eliminating approximately a third of the Mosquito Commission staff with some people having departed by the time of the case in September. Others were to be laid off shortly thereafter. The administration was using phrases like "We have to do more work with less money," and "We have to get by with what we have." I responded that "We have a case of malaria we have to explain."
I noticed that after a short time, the questions from the elected officials and the general public fell into two categories. One category was the general question of how can there be a malaria case around here, "That's a tropical disease," and the other category was "So what, I've heard of malaria but what's new about it?" To develop an answer to both questions, I turned to the proceedings of the New Jersey Mosquito Control Association, With a brief history of malaria in New Jersey, Camden County people who were confused and downright skeptical of a case of malaria in their area became believers.
When I could cite the history of this disease in their town, their neighborhood and within the lifetime of their parents or grandparents they accepted the new case more readily. This overcame much resistance and gained their interest and willingness to learn and follow the story further. Having developed this trust, we were then able to present a description of our light trap network, our inspections and surveillance and our plans. This made us appear very professional, prepared and in control of the situation.
We went back in our own records and prepared graphs of surveillance information keying in on the Anopheles quadrimaculatus as well as the traps and surveillance data from the area around the case. The trend of increasing numbers of Anopheles quadrimaculatus had been noted a few years before by our Identification Specialist, William McCombs. Having discussed this in house, we had begun using, during the 1991 season, Aerosurf as a control for anopheline species. We had also conducted a refresher course on dipping techniques for the collection of larval anopheline species. We reviewed the surveillance information back a number of years, back to a time when the Clean Water Act went into effect and precipitated in Camden County development of a regional sewage disposal system. This resulted in the diversion of more than a hundred million gallons of sewage, treated to various degrees, from many local streams and rivers and now processed through a very efficient system and delivered directly to the Delaware River.
Looking at light trip information, which of course is a poor indicator of Anopheles quadrimaculatus populations, there is a steady upward trend; while looking at all species, there are the various cycles that you might expect are driven by the weather conditions in the various years. But while these trends seem to hold for the County in general and may indicate an influence of the ever improving quality of surface water in the County, the locally acquired malaria case came from a part of the County least impacted by the regional sewer system. An area that had good surface water quality. Camden County like most of south Jersey has a tremendous range of types of habitat for many species of mosquito. The County extends from the highly urbanized and industrialized portion bordered by the city of Philadelphia and the Delaware River to areas well within the pinelands of central New Jersey. This rural part of the County is interspersed with many natural and/or very old man-made lakes and ponds. It is now also dotted with very new ponds in the form of retention basins. Most of these water bodies are now in proximity to housing developments and other population centers.
As was reported earlier, the locally acquired case and the suspected importer of the malaria lived about a mile apart in an area of predominantly working farms interspersed with new housing developments and apartment complexes, and these residential areas bringing with them their own mosquito habitat in the form of basins. Many of these basins are fenced, making inspection either difficult or very time-consuming.
Having received notification of this case, we took actions such as putting out resting boxes and preparing for additional treatment. The layoffs had caused us to use supervisors in what normally would have been inspector positions. We were simultaneously looking at an eastern equine encephalitis problem in an area a few miles away. Light trap and resting box information from that area was alarmingly high very early in the season. Record high numbers of melanura were present in the resting boxes used by the vector Surveillance Program run by the Experiment Station and the State Commission. By the time of the malaria case, we had twelve EEE isolations from the resting box station in Camden County. We then had to explain to the administration that the Commission did not want to divert efforts from the area at risk from EEE. Any reasonable person would rather have a case of malaria than a case of eastern equine encephalitis. Therefore, what little additional resources we could muster continued to go into the area of eastern equine encephalitis isolation and potential human involvement. We did as much additional work in the malaria concern area as we could and we forwarded our historical as well as up-to-date information to Dr. Crans who was sharing it with the State Health Department and sending it directly to the National Centers for Disease Control. We took the additional step of contacting mayors of the municipalities in the immediate area. We delivered to the municipal office handout literature on mosquito control such as brochures from Rutgers University as well as one developed by the Commission on personal protection specifically for this incident. The elected officials and administration in the County responded by delaying some of the layoffs and allowing us to finish the adult mosquito season with the staff present when the incident was announced. This year the County as a whole is looking at additional layoffs, but the Mosquito Commission expects to hire back four employees. The elected officials at that time as well as a new administration took the matter seriously and very quickly came to trust the opinion and prediction expressed by the Commissioners.
Specifically to this case, it is interesting to note that the victim lives in an apartment complex and in fact in the apartment closest to the retention basin for that facility. It is also noted that the other residents of the apartment complex shunned this patient apparently out of fear of contracting malaria directly from the individual during her illness. It is unfortunate that the public does not know and didn't come to know clearly from reports on this subject that the mosquito was a necessary step in almost all transmission of this disease. So while the public may not know the scientific details, they, I suspect, would not want to give up mosquito control any more than they would give up indoor plumbing. Whether their first reaction would be that this would bring back certain diseases or simply it would not be aesthetically appealing, the overall answer would be "No, we want to keep our indoor plumbing." It is important that the public be periodically reminded that professional mosquito control is important to them for nuisance control value and disease control value.
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