Lomborg-errors: "Cool it!"

More illness: malaria in Vermont?
 
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  Comments to pages 92 - 102 in Cool it.

THE WHO STUDY

(COMMENT)
Page 93 top: ". . a headline like `Climate change death toll put at 150,000´ sells a lot of newspapers"
Comment:
Lomborg does not mention that due caveats are mentioned in the press release, for instance this: "But he acknowledged global deaths from climate change were minuscule compared with the total number of deaths a year, which the WHO puts at 56 million. About 10 times more people die each year from tobacco-linked illness, he said."

(COMMENT)
Note to page 93: "The analysis was redone in 2005 . . . "
Comment:
The reference from 2005 is not a remake of the analysis, but a review dealing with the WHO analysis as well as with many other studies. It does, however, contain some information that was not included in the chapter in the WHO report.

FLAW
Note to page 93: "They only have old and very limited surveys for these results. . ."
Flaw:
This is not true. The surveys for hot climates are completely new. It is true that for Europe they only use Kunst et al. (1993). Between the lines, Lomborg suggests  that  this  study is old  and hence outdated and not so reliable as newer studies. On the contrary,  the WHO report argues why  exactly this study is better and more reliable than others. In any case, the changes in death rates are mainly in warm climates, and therefore the finer details concerning deaths in Europe are of little importance.

(COMMENT)
Note on page 93: " However, there are no `reasons described above´ anywhere . . "
Comment:
The source gives many reasons why the data are of doubtful value on its page 142.

ERROR
Page 93 and note: " . . they simply left out cold and heat deaths . . ." In the note: "In the 2005 update . . they equally leave them out of the total (Patz et al. . .)"
Error: This is directly wrong. The net effect of cold and heat on cardiovasular disease is actually included in the table referred to by Lomborg on page 312 in the 2005 paper. When Lomborg tells his readers that Patz et al. left out the data, and they clearly did not, this is deliberately misleading.

ERROR
Page 93: " . . leading to the total death toll of 153,000."
Error: The primary source, Campbell-Lendrum et al., does not give any total death toll. The secondary source, Patz et al. 2005, gives a total death toll of 166,000. It seems that Lomborg has subtracted the figure of the death toll due to cardiovascular disease of 12,000, although the result of this (completely unjustified) subtraction is 154,000 rather than 153,000.

FLAW
Page 93: " . . . we get about 620,000 avoided cold deaths and 130,000 extra heat deaths."
Flaw:
This calculation is made on the basis of Bosello et al. (2006). As explained elsewhere on Lomborg-errors, the data go back to Martens (1998), which has a flawed treatment of the data. In the original data, the increase of heat-related deaths more than outweigh the decrease in cold-related deaths, but on the basis of these data, regression formulae are made which give just the opposite result.

ERROR
Page 93 bottom: ". . there are actually almost 200,000 more people surviving each year. "
Error: First, Lomborg´s calculation is wrong. If we use the figures that he mentions in his text, we obtain the following net change in number of deaths per year: -153,000 + 620,000 - 130,000 = 337,000. Second, the figure cited by Lomborg is just the outcome of one calculation, based on the misuse of original data in Martens (1998). The alternative data in Patz (2005) is that the net effect of cold and heat is an increase in cardiovascular deaths of 12,000 per year. So, one calculation, which is probabaly flawed, gives a net result of +200,000, whereas another gives -12,000. Considering the uncertainty indicated by the difference between these two estimates, it is very misleading to use the word "actually", as if this were well-established fact.

ERROR
Page 94 top: "Had all the relevant data been included, it would more likely have shown the very opposite picture."
Error: This is completely wrong. All the relevant data have indeed been included, and the result is 166,000 extra annual deaths. Lomborg knows this (he has studied the relevant table in Patz et al. 2005), so his text is delibearately misleading, and very grossly so.


MALARIA

SOME GENERAL COMMENTS:
Lomborg uses several pages (pp. 94 -97) to explain that the distribution of malaria is mainly governed by socioeconomic conditions, whereas climate causes no serious restriction. Indeed, malaria may occur in very cold climates, such as Finland and Siberia, but one should not exaggerate the ability for malaria to thrive in cold climates.
    There are several species of malaria parasites. The most deadly is Plasmodium falciparum, which is widespread in the tropics. Another species, Plasmodium vivax, is more widespread in subtropical and temperate climates and is of little concern in Africa, because most tribes/races of Africans are resistant to it. P. plasmodium can hardly develop in its mosquito host at temperatures below 18° C, whereas the corresponding limit for P. vivax is 16° C.
    Details concerning the climatic conditions limiting P. falciparum in Africa are given on this page in Lomborg-errors. As described there, the number of months with temperatures above 18° is crucial. When every month is above this temperature, the parasite may infect at any time of the year. Children will be permanently exposed, and they will gradually develop immunity. However, if some months are too cold, infections occur only seasonally. And if temperatures are not high enough every year, infections will occur only in certain years. Contrary to what you might expect, the latter situation is the most dangerous, because then children will not have developed immunity. Malaria will then occur as epidemics in certain years, and in these years it will kill thousands of children.
    Similar situations may arise in northern Europe or Asia with Plasmodium vivax. This parasite species exists in several forms; the northernmost form does not become infective until it has spent about 8 months in its human host. That is, when people are infected in late summer, the parasite survives in them during winter, and become infective only in the next spring. The life cyclus may be completed if only summer temperatures remain above 16° C for at least one month. But in some years, summer temperatures may become much higher. For instance, temperatures at Arkhangelsk in the summer of 1935 were up to 35° C, which means that during the season when the parasite is in the mosquitoes, it may be subject to "tropical" temperatures, and the development within the mosquito host will be extremely rapid, allowing very fast reinfection of humans. If there are two or three hot summers in a row, the parasite may multiply enormously. Under these conditions, most people have not previously been exposed to the parasite, and have developed no immunity. When there is a sudden mass infection with malaria parasites, they will therefore become very ill, and if they are not treated, many will die. This is the explanation why we hear that mass mortality due to malaria has occurred in northern climates.
    If the climate warms generally, the risk to have series of such hot summers increases, and epidemics may become more frequent.
    At intermediate latitudes, there may be a spreading of other forms of P. vivax which develop fast in their human host and are able to reinfest mosquitoes already after 3 or 4 days. This allows them to have several generations during a summer, and thus to have multiplied considerably by the end of the summer. There may then be a trend towards seasonal increase in malaria infections every year.
    It is therefore much too simple to claim that malaria may occur in the tropics as well as in Finland and Siberia, as if changes in temperature would have little consequence. Even small temperature changes would easily lead to large differences in the prevalence of malaria.
   All this concerns a situation when no chemicals are available to fight the malaria parasite or its mosquito host. It is not possible to eradicate the host - only to decimate its numbers temporarily. On a short term, however, this is enough to break the life cycle of the parasite and thus to eradicate it. For instance, in the years following the Second World War, spraying with DDT eradicated malaria in the Soviet Union. USSR  was declared free of malaria in 1960.
    There is always a risk that the parasite may return, however, because the Anopheles mosquitoes will survive, and because people travelling around may carry the parasite with them. Local mosquitoes will become infested when feeding on migrants, and thereby a local cycle of transmission to resident people will be initiated. This is happening to an increasing extent. In Russia, especially around Moscow, the number of cases of local origin has been growing. Thus in 1998 there were 1,019 "imported" cases and 63 of local origin, while in 2002 the corresponding figures were 764 and 134. Malaria has been imported mainly from Tajikistan, where the disruption of civil war combined with an influx of malaria-carrying refugees from Afghanistan has generated the first post-Soviet malaria epidemic (source: this link).
   If a local cycle of infections starts e.g. at Moscow, it will be interrupted by finding all infected people and treating them with anti-malaria drugs. However, malaria strains resistant to the commonly used drugs are becoming more widespread in South Asia, and may be carried to Russia with immigrants or tourists.
    A similar situation may arise in USA if tourists or migrants import drug-resistant forms of the malaria parasite, e.g. from Mexico or other Central American countries.
    Historically, the malaria parasite has developed resistance to anti-malaria drugs, first to quinine, then to chloroquinine, then to pyrimethamine, and now the very first examples of resistance to artemisinin-derivatives are being reported (for instance this link).  A new cheap anti-malaria drug seems to be underway now (link), but in the end the question is: who wins the race between man and parasite: will the parasite develop resistance faster than man can find new drugs? Once resistance to artemisinin becomes widespread in future (which may very well happen), there may remain no efficient anti-malaria drugs, and if man becomes the loser of the race, there may come a time when malaria cases in highly developed countries will no more be treatable.
 
(COMMENT)
Page 98 top: ". . . DDT, which is still the most cost-effective insecticide against mosquitoes  . . "
Comment: Rosenberg (2004) says: "Both bed nets and house spraying can be effective, and studies comparing costs differ on which is cheaper." Schapira (2006) Says: "Few trials have compared insecticide-treated nets [impregnated with pyrethroids] and indoor residual spraying [with DDT], but results so far suggest that the methods are more or less equal in efficacy." Walker (2000) says: ". . the prices of pyrethroids are declining, making some only slightly more expensive than DDT at low application dosages."

(COMMENT)
Page 98: ". . . which has made it easy  to claim that global warming is the culprit."
Comment: This is not a fair summary of the references by Epstein and Patz noted for page 98. Especially the paper by Patz et al. (2005) does not make easy, general assertions. Rather, it says that several studies "have not found a link to temperature trends, emphasizing instead the importance of including other key determinants of malaria risk such as drug resistance, human migration and immune status . . ". See also the Lomborg-errors page on malaria in Africa here.

(COMMENT)
Page 98 bottom : ". . . the malaria parasite is becoming resistant to it. There are new and effective combination treatments based on artemisinin available . . . "
Comment: Optimism concerning the possibility to reduce malaria or to keep it away where it does not occur now is corrupted by the development of resistance to anti-malaria drugs. The very first examples of resistance to artemisinin-derivatives are being reported (for instance this link).  Once resistance to artemisinin becomes widespread in future (which may very well happen), there may remain no efficient anti-malaria drugs.

FLAW
Page 99: " . . researchers tried to see whether more people at risk would actually lead to more malaria. "
Flaw: The paper cited by Lomborg (Rogers and Randolph 2000) states in its abstract: "These results were applied to future climate scenarios to predict future distributions, which showed remarkably few changes, even under the most extreme scenarios." Therefore, what is referred to here is predictions of the geographic distribution of malaria parasites in the future, which by their very nature are uncertain. And no measures of society´s ability to fight malaria e.g. by drug treatment is included in that paper. It is therefore wrong to postulate that the paper investigates whether there will actually be more malaria.

ERROR
Page 101: " . . . it seems likely that the continent [Africa] will cross the $ 3,100 threshold around 2080. "
Error: The $ 3,100 threshold is taken from Tol & Dowlatabadi (2001) and is extremely uncertain. The figure is obtained by excluding regions that do not fit into the general pattern, especially Africa. So it is not valid for Africa.

FLAW
Page 102: "The problem is that often the climate argument is virtually the only one offered."
Flaw: The press article referred to is no longer on the net. However, one may search the archives of that source, chron.com, which gives access to many newspapers. Searching for the period 2001-2007 for articles with titles containing the word `malaria´ in combination with either `climate´, `CO2´ or `rising temperatures´ gives just one hit, from the same date and with the same author as the article cited by Lomborg. Also, in scientific articles referred to by Lomborg, for instance the paper by Patz et al. (2005) referred to above, the climate argument is certainly not the only one offered, contrary to Lomborg´s claims.

FLAW
Page 102: "However, WHO finds that the real reason for the reemergence of malaria in Kenya is not climate change . . . "
Flaw:
The WHO report does not say that. It refers to a number of studies finding a possible relationship between changing climate and changing prevalence of malaria. It goes on to say that these studies have "garnered popular interest among the wider scientitific fraternity", which in turn has stimulated the tendency to link all phenomena to popular scientific themes. And it criticises this tendency. But it does not claim that the studies referred to had made wrong conclusions. Instead, it says that the genesis of epidemics is multifactorial, and that in a number of cases, climate does affect malaria incidence. For instance, El Nino rains have had such effects. The text then proceeds to discuss the cyclical pattern of epidemics occurring at intervals of a few years, and concludes that temperature data cannot explain this cyclicity. Lomborg misreads this part of the text and gets the impression that temperature is without importance for the incidence of malaria.