A lady with wounds caused by the weed, left, seen growing in Busia
A lady with wounds caused by the weed, left, seen growing in Busia
There’s some kind of terrible poisonous weed like this right here in Ohio. Ever year we get warned about how it’s taking over. Forgot the name though.
The “Congress” weed once found its way into India through American wheat shipments in the 70s.
The “Congress” part of the name comes from the white flowers, similar to a white military-like cap that the Indian Congress political party workers used to wear.
Other than causing asthma through its pollen, I’ve never heard of the plant causing skin wounds.
Maybe this is another variety.
A few guys with some war surplus Flamenwurfers ought to work -- assuming you can persuade them not to point them at each other (this is Africa after all). If that would work I can't see this being a multimillion-dollar problem.
First Killer Bees, Ebola,Obama,and now this?There’s all kinds of nasty things that come out of Africa these days.
Parthenium: A wide angle view.(SEMINAR)(Parthenium hysterophorus L.)
The Indian Journal of Dermatology, Venereology and Leprology
Publication Date: 01-SEP-07
Author: Lakshmi, Chembolli ; Srinivas, C.
Byline: Chembolli. Lakshmi, C. Srinivas
Introduction
Parthenium hysterophorus L. (congress grass, congress weed, carrot weed, wild feverfew, the "Scourge of India") is an exotic weed that was accidentally introduced in India in 1956 through imported food grains.[sup] [1] It has become a common weed causing dermatitis of epidemic proportions.[sup] [2] The epithet "congress weed" refers to the US congress (who allocated the shipment for Pune, India).[sup] [3] In Pune, it found an ecological niche without natural enemies and spread rapidly along the canal banks, roads and railway tracks to become a major field weed.[sup] [4] Both rural and urban areas have been invaded by this weed. It is the leading cause of plant induced air-borne contact dermatitis in India[sup] [5] and has achieved major weed status in India and Australia within the past few decades .[sup] [6] The weed can affect human health, animal husbandry, crop production and biodiversity.[sup] [6]
Distribution
Parthenium hysterophorus is a native of the West Indies and North East Mexico.[sup] [7] During the last hundred years, it has spread worldwide [Table 1].[sup] [8],[9],[10] It is thought to have originated as a result of natural hybridization between Parthenium confertum and P. bipinnatifidum .[sup] [11]
Botanical Aspects of P. Hysterophorus
It belongs to the family Asteraceae/Compositae (Daisy family), which is one of the largest and most important families in the plant kingdom. The family includes troublesome weeds, ornamental annuals, herbaceous perennials, medicinal and food plants [Table 2].[sup] [12],[13] Fifteen species of Parthenium L. occur in America and the West Indies. One species, Parthenium hysterophorus L. was introduced to the Indian subcontinent. All contain allergenic sesquiterpene lactones (SQLs).
In South America, P. hysterophorus does not contain parthenin, but instead has hymenin, which is a diastereomer. However, in India, the plant contains large amounts of parthenin and ambrosin.[sup] [14] No cross reaction between parthenin and hymenin exists in humans and guinea pigs.[sup] [14],[15]
The plants of Compositae family have many tiny flowers (florets) clustered to form a flower head (capitulum). This flower head is surrounded by bracts (modified leaves) that form an involucre beneath or around a flower cluster [Figure 1].[sup] [12]
P. hysterophorus has two life cycles,[sup] [8]
*Juvenile or rosette stage *Mature or adult stage
Juvenile stage
It has a rosette with large, dark green, simple, radicle, pinnetisect small leaves and flowering is absent. The large lower leaves are spread on the ground like a carpet, without allowing any vegetation underneath it.
Adult stage
It is procumbent (trailing along the ground but not rooting), profusely branched, leafy herb resembling a bush or shrub because of its height (1-2.5m). The stem becomes tough and woody as the plant matures into a hardy bush. Enormous number of pollen grains (624 millions per plant) are produced by anemophilous (by wind) pollination. It is an extremely prolific seed producer with upto 25,000 seeds (achenes) per plant. The plant is thermo- and photo-insensitive; hence, it grows round the year except in severe winters; in other words, it survives environmental extremes. It is a rapid colonizer and competes out other vegetation in its vicinity within two growing seasons. It grows in almost all types of soil except near the seashore as the saline soil is not conducive to parthenium flowering.
Allergenicity
The allergens in Asteraceae are SQLs and thus the patients with contact dermatitis to Compositae can react to many other non-Compositae SQL containing plants [Table 2].[sup] [12],[13] The SQLs are found in the leaves, stems, flowers, and some pollens. The highest concentrations are found in trichomes which are present on stems, the underside of leaves and in the flowering heads.[sup] [12]
Cross-reactivity between SQLs does not follow any rules. No single SQL nor the commonly used " SQL mix" of three common SQLs (alantolactone, dehydrocostus lactone and costunolide) serves as a reliable screen for SQL allergy.[sup] [16] Therefore, the samples of the suspect plant should always be used while patch testing a patient.[sup] [11] Over 200 skeletal types and 1350 individual types of SQLs have been described, and each of these may have multiple functional groups attached to them.[sup] [12]
SQLs are characterized by the presence of a a-butyrolactone ring bearing an exocylic a-methylene group [Figure 2].
Human health
Around three decades ago, serious human health risks from P. hysterophorus were reported from Pune.[sup] [1] Several thousands of cases of allergic contact dermatitis with some fatalities have been reported.[sup] [1] An outbreak of epidemic proportion followed a dam burst.[sup] [2] "After 1-10 years of exposure to the weed, 10-20% of the population will develop severe allergenic reactions. There may be hay fever, asthma or dermatitis and can be caused by dust and debris from the plant as well as pollen."[sup] [17] The severity of dermatitis in India is greater in comparison to America because the plant grows more vigorously in India and contains large amounts of the sesquiterpene lactone, parthenin, which is absent in the plants in South America.[sup] [18],[19]
It clinically involves the adult males in both USA and India.[sup] [12],[20],[21] Studies have estimated a ratio of 20:1 between men and women.[sup] [3],[12] This cannot be explained in terms of degree of exposure since Indian women and children also work in fields. Possibly women and children are less frequently sensitized.[sup] [12],[21] However, the studies on plant dermatitis from India have shown a male-to-female ratio of 1:1 and 5:5:1.[sup] [22],[23] In a study from Minnesota, the large male preponderance appeared to change with the male-to-female ratio of 1.4:1.[sup] [24] Initially, the exposed sites of the face, neck and flexures are affected with erythema, blistering and intense pruritus resulting later in skin thickening, hyperpigmentation and development of a leonine facies.[sup] [1] Unexposed sites may get involved late in the course of the disease. A seasonal variation is initially observed with the dermatitis flaring in the summers corresponding to the growing season and disappearing in winters.[sup] [25] After several years, persistent pruritic lichenified dermatitis develops without seasonal variation. Winter exacerbation is seen in the months of September, October and November and may be due to the...
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now if we can just cross it with kudzu and send it wherever...