Portugal is not a tropical malarian country - clarification

There's a strange censorship now at LP.

I'll have to create a new thread so as to post a clarification about a question about Malaria.

First of all, the malaria cases reported in Portugal or elsewhere in Europe are not gotten in Portugal. These people were infected in tropical countries by people who alfterwards came to Portugal. The same cases happens everywhere if a temperate country has many direct flights to tropical countries.
Malaria is given by a parasite of a mosquito that does not exist in Portugal. That mosquito only exists in humid tropical (or subtropical) areas in the world. This is not entirely about being "developed" or "developing", although the lack of resources, knowledge and will also help to let it happen.
Southern China f.ex. has tropical climate, Portugal or Greece, or Spain, or Malta, or Italy, or Cyprus do NOT have tropical climate. Southern Europe is a mediterranean climate region. This kind of climate has a dry summer (it's also known as dry summer climate), not really prone to tropical infections due to the lack of humidity, despite the heat.
As you're American, your nearest example or mediterranean (or dry summer) climate lie in California. I assume, unless you're an obsessive hypocontriac person, that you wouldn't take malaria pills for visiting San Francisco or Sacramento, would you? But you would probably do it if you decided to go to the Mississipi delta or to Florida in the summer (humid subtropical climate regions).
Mainland Portugal lie between the paralels 37 and 42 north.
Having said this I am going to give some comparisons with the US
- a) 37º and 42º are the latitudes of the state of Utah.
- b) It's equivalent to the central and northern parts of California. Paralel 42 is also the northern border of California with Oregon.
- c) Lisbon lie at paralel 38, 70..., roughly the same latitude of Washington D.C., slightly northwards than San Francisco, CA.
- d) Oporto, Portugal's second city, lie at paralel 41, roughly the same latitude of New York city.

These latitudes are too northward to have tropical infections, unless climate change will change the climate patterns in the future. Hence the fear of starting to have these sorts of desease in the future, but up until now, yes, it's too northward for tropical desease to spread.
Andreas: Fear, or risk is not the same as "it exists". You haven't answered any question.

Regarding Madeira Islands, it's a slightly different story. Madeira lie 1000 kms far from Lisbon between the paralels 32 and 33. It's latitude as well as climate is comparable to that of San Diego, CA. The climate is also mediterranean with a dry summer period, however it's at the southern boundary of the mediterranean climate area, so it has a subclassification of "mediterranean subtropical". It's not in the tropics, but it's close. Last summer an outbreak of dengue made its first appearance in the island. It had never happened before.
I was told that during this winter there were no new cases of dengue because apparently the tropical mosquito that carries the dengue did not like the winter "too cool" of Madeira. You may laugh at this, but yes the mild winter of Madeira is too cool in comparison with REAL tropical countries such as Senegal, Gâmbia, Cuba, Caribbean Islands, Central America, etc.
It's actually more likely to happen in the Canary Islands than in Madeira, because the Canary Islands are farther south.
Dengue is also endemic in the subtropical "south" of the US (Florida, Louisiana, Alabama, Georgia) or in Australia.

Now, I see that Americans do not have a clue about Europe. They tend to compare the warm southern regions of Europe with their subtropical south. It's not the same. Europe in general is northwards than the USA, so Southern Europe is at the same paralels of central, even northern USA. Besides, Europe is the western part of the great Euro-Asian contiment, which give for much of the continent a "west coast" climate type similar to that of western USA and Western Canada.
Saying that Rome, Italy, or Portugal has a humid summer is simply non-sense. Humid hot summers happen in New York, in China, in Japan, in Buenos Aires, not in West Eurasia Europe.

Got it?

Joaop - thanks for a very informative post. The reason you had to commence a new post was that the moderator stepped in and closed the original posting to any further posts. Again thanks.

Ditto as #1, joaop.

I think closing the thread was due to being thinskinned of some posters and then you're not only susceptible of mosquitos;-)

Thanks joaop, i think 99% of us is well aware of this.

Still, for the sake of completeness i think we should not forget that malaria did occur in Europe (but also in the US) and not only in mediterranean countries.
Take Italy as a case, malaria was totally eradicated by the end of the 1950's if i am not mistaken, only a few generations ago.
http://www.mjhid.org/article/view/9990/html
http://www.pri.org/theworld/?q=node/4288

There's a strange censorship now at LP.

No, there is not.

#2 has it right. The thread was closed because the original questions had been answered, and the OP seemed to ignore the answers, preferring to indulge a persecution complex. In my reading, there was nothing that needed clarification about malaria. The OP was a worrier and overreacts .. as her own behavior on the thread illustrated.

Thanks Joao....we know it,but some of the less travelled new posters may not be aware of it,so this clarification should help allay their fears...

Malaria is given by a parasite of a mosquito that does not exist in Portugal. That mosquito only exists in humid tropical (or subtropical) areas in the world.

Uhhh... malaria is endemic to Portugal, it existed there as well as other countries such as Italy and France, and was not eradicated until after World War II when DDT spraying was used. Full eradication of malaria in continental Portugal was achieved in only 1958.

The only reason there is no malaria in Portugal today has nothing to do with climates, latitudes, or what USA state is at the same latitude (seriously?), but DDT spraying.

The point is whether it exists now or not,no?

And the answer is...no.

So you can go to Portugal without fearing catching malaria....

The point is whether it exists now or not,no?

I agree that is the point Luca, but that doesn't make joaop's explanation why fully correct ;-)
Not about Portugal, but some interesting facts...
http://www.reuters.com/article/2012/11/23/us-malaria-greece-idUSBRE8AM0BC20121123

I usually hang out on the Health Branch, but every so often I do a search on words like "malaria" to see what's being talked about. So I stumbled across this thread. Maybe I can clarify a couple of things.

Malaria is spread by mosquitoes of the genus Anopheles.+ There are hundreds of species, living all over the world, including temperate parts of Europe. 41 +Anopheles species are known to be able to transmit malaria well enough to cause significant human illness and death. They can be found just about everywhere that is not the Antarctic. However, the climate has to be relatively warm for malaria species to complete their life cycle in the mosquito. Not super warm--malrai was a problem in England & the Netherlands, for instance.

Anopheles atroparvus was the primary species that transmitted malaria in Portugal, and the mosquito is still found there. It isn't very good at transmitting the species of malaria that is most likely to kill, but is good at transmitting the species that used to predominate in Europe. There are 4 other species of mosquito found in Europe that are known to be good at transmitting malaria.

According to a scientific article published last year "Malaria is a notifiable disease in Portugal; about 50 cases are reported annually to the Public Health System, but cases are under-reported [mainly due to the effort needed to get the forms filled out]." These cases are all imported, that is, the person got the malaria in another country, but it was diagnosed in Portugal.

Malaria risk increases in Portugal from July, 2012.
>The director of the National Health Service, Francisco George said this week there were 58 imported cases of Malaria in Portugal last year. Although no new cases have been contracted in the country since 1959, the risk of it returning to the country is expected to increase with climate change.

According to a statement from the National Health Service, "the last cases of Malaria contracted in Portugal were diagnosed in 1959" and "since then, all other cases identified in Portugal were imported and contracted by travellers who returned from tropical countries."

Eradication of malaria in developed countries relied on a number of things. Spraying for mosquitoes and eliminating breeding areas was very important. But improvements in economic and living conditions also contributed a lot.

Dwellings with door and window screens. This is big. In Africa, it's been demonstrated that sleeping under bed nets is one of the most important things in preventing malaria.

Getting rid of outhouses, cesspits, and other such places where mosquitoes could breed. Covering water tanks. Paving streets so puddles don't sit around ling enough to become breeding sites.

Development of better ways ot diagnose and treat malaria. The faster you can get people free of parasites, the less likely a mosquito is to become infected.

Access to health care for most people, so they can be effectively treated.

Ok, sorry once again ladies and gents for not being completely accurate, but again, those recent malaria cases were imported.
I am pretty sure that that happens in any country with ties to tropical zones. People travel more and more. Planes present an increased risk of carrying infections and bugs.
It does happen that Portugal has centuries old ties with Africa. From Lisbon's airport there are regular flights to many African countries, to Florida, to 10 different cities in Brazil, to Venezuela, plus charters to the Caribbean. People infected may come here as they may go elsewhere, hence the detected cases.

I did not know that there had been malaria here. My mistake, sorry. At least I triggered an interesting debate. I read somewhere that the vector mosquito exists in marshlands by the river Sado and the Guadiana River, to the south and east of Lisbon, and yes, I've been to towns by the Sado river in the summer and there are plenty of mosquitos, because there's heat and fresh water. Apparently it's the malaria germ that does not exist in the (female?) mosquito, or at least the tropical kind of.

Again, the long term fear is that, with global warming and climate change, many temperate zones including Portugal will again have malaria or other tropics associated deseases. Long term means the next 50 or 100 years?Other countries? Many you wouldn't think of. A hot summer in Finland, Russia or Sweden may pose risks? There are plenty of mosquitos there, plenty of fresh water pools and warmth induced by greenhouse gases is exactly what mosquitos love. What about Canada and the US mid-west? humid Germany or Netherlands in a heatwave summer? New Zealand's cold turn warm South Island? Tasmania? subpolar Tierra del Fuego?

Thanks Nutrax for the clarification.

At least I triggered an interesting debate.

Yes joaop, i do think it is an interesting and eventually worrying subject.
Imported cases of malaria (from people who have been infected abroad) occur everywhere.
In Belgium where i live there has been malaria until 1938. Global warming could certainly have its consequences. Several species of mainly insects and birds have been detected to be moving north already.
The (very limited) malaria risk in Greece (see article above) which i think is relatively recent proofs that vigilance is needed, and that we can't automatically assume that malaria will remain eradicated in (southern) Europe forever.

On a side note, i will not worry at all when travelling to Greece ;-)
According to the reputable Institute of Tropical Medicine in my hometown the risk is extremely local and very limited:
Very limited malaria risk (P. vivax only) may exist from May to October in villages of the Evrotas delta area in the Lakonia district (an area of 20 square km) in agricultural area with large migrant populations. There is no risk in tourist areas.
http://www.itg.be/itg/GeneralSite/Default.aspx?L=E&WPID=136&miid=333

In the outbreak of malaria that has occurred last year or so in Greece, about a third of the cases were Pakistani farmworkers in a couple of rural areas. For some of the workers, it could not be determined if they acquired the malaria in Pakistan or Greece. Other cases were clearly locally-acquired or clearly imported. The US CDC reported on Jan. 113
>Cases of malaria continue to be reported in Greece. Some new cases have occurred in areas of Greece where malaria had not been previously reported. Cases of malaria have been reported from the Attica, Karditsa, Laconia, Viotia, and Xanthi regions of Greece. Cases have occurred in the cities of Evrotas, Marathon, Markopoulo, and Selino. No cases have been reported in Athens. The Hellenic (Greek) CDC and the European CDC are improving surveillance for malaria cases. In affected areas, mosquito control has been intensified, health care providers have been educated, and the public has been informed.

The kind of malaria in this outbreak is not going to be a problem in winter, but there will probably be additional cases when weather warms up.

Let's all just give thanks for the effectiveness of DDT decades ago, which eradicated the mosquitoes carrying those diseases in the various zones mentioned above (because today DDT is not tolerated).

On a related note, today in poverty stricken countries there are millions of avoidable deaths that are related to malaria, yellow fever, dengue fever, etc, that ARE tolerated... as long as it means DDT remains banned.

Amokinsa, DDT contributed to erradicate malaria in many places: USA, Italy, etc. If that on the other hand caused an ecological disaster, contaminated fresh water and soils and caused cancer to many people, we should see the balance of that: were there more deaths caused by malaria or more deaths caused by DDT? Besides there were cases of germs being resistant to DDT.

As far as I am aware, there are things that can be done without using DDT and using little money. Putting leads in all the tanks with fresh stagnated water is one of them. Even roofing canals and dams. Dams are man-made. In tropical countries, they present a risk because of all the fresh water there. The ecological change is already done with the consttruction of the dam, so why not closing it with a roof?

Using air conditioning and electrocuters of insects involves having extensive electric supply to homes. Air conditioning is expensive but using those electric plug ins maybe does not spend so much electricity, probably can be done with a battery and a solar pannel and are effective.

Again back to Europe. The risk being in marshlands by rivers, not on seaside beaches with plenty of salt water and salt spray. Again the summer is DRY, so mosquitos only exist by river banks and swamps.
The winter can be above freezing in many coastal areas of Southern Europe, but it freezes and snows in the mountains, plateaus, inland areas and sometimes on the coast. It's likely in Greece to fall snow in the winter, much more often than in Portugal due to its easterly continental location. Those deseases really hate the winter.

Mredman: climates have a lot to do with that. You're right if it's not the only reason, but you're wrong if there's nothing to do with that.
When I hear Americans coming to Lisbon in November, and complaining about rain, thinking it's unseasonly (????), It comes to mind that they think that Portugal is a tropical country with a dry season sarting in November (???), and a wet season in the summer? It is not!

OK - enough again. Mod I think we can close this one!!

In the case of this thread i would leave that honour to the OP orion_mike.